-I understand the game says your bones(s) will heal slowly, and IRL it can take a really long time, but I made a splint and put it on almost immediately and it’s been over three in-game days and I have yet to be better. 
-I can survive fairly well since Keith somehow has the same superpower as my dad (surviving near-death experiences every time). But even so it’d be much easier to survive with proper arm protection and not constantly running out of stamina due to arm encumbrance. It almost makes hunting the many hundreds of pigeons nearby for food far more difficult.
A couple weeks I think. Never dealt with it myself, for some reason they’re more likely to break my legs than my arms and that usually winds up a death sentence with me moving too slowly to run away from the zombies that are killing me.
It can take a few days depending on your traits, but the most important thing is not to get hit. If that bodypart is hit even once then the timer resets.
Last I heard, health (not HP) contributes a large amount to deciding when breaks mend, so if you’re still using that Cyberjunkie, it’s going to be a while.
Several times I’ve broken limbs trying to remove broken bionics with the Broken Cyborg, and I once waited for nearly the entirety of a 91 Day season for broken legs to heal, to no avail.
If your computer skill is high enough, you can find a Hospital, and if it has a Mr. Stem Cell machine, hack it and use it. It instantly cures breaks. There’s a chance that it will do damage to all body parts instead however, so don’t use it if your head and torso are near 0 as well.
If you started the game as a licenced medical professional, you don’t need to hack it (and get a hefty bonus to installing bionics to boot!)
-Well, my leaky bionic is finally gone, so health isn’t too much of a problem now. I got it out with a 74% chance of severe bodily damage but I was all like: “Eh, Keith is immortal despite being a noob with low skills and lots of disadvantages. It’ll be fine.” His torso was at one bar at the end but that stupid leaky bionic is out now.
-I’m not certain how I’m supposed to avoid getting my arm hit around my ‘home’ since while I cleared out the majority of enemies there is always a couple wandering around nearby. And of course I need to still loot the town nearby, since food is a little bit of a concern. (There is a massive amount of pigeons but the broken arm makes it so I have about a 2% chance to hit it. And while pigeons are not the smartest they know to leave when I go too close to them.)
-I don’t actually know where a hospital is as of yet, sadly.
-I’m fairly certain the only reason Keith is alive is because of the 100+ vitamins he found really early on…
Scavenge bushes for wild vegetables, they are quite nutritious. No need to risk your hide in cities. So 'go vegan" while you recover? 
-Hmm, that would work I suppose. How do you scavenge bushes though? Is it basically just smashing them repeatedly? Luckily, unless there is no rain for a week in game, I’ll never run out of water with what I store water in. I can’t remember the name but it holds a lot of stuff in it. It was a present from the neighbor next door, sadly, he also wanted to eat my brains. As said previously, Keith is immortal, so while it hurt a lot it was fine!
No no, don’t smash them. Examine them with ‘e’, if you use something like Chesthole tileset they will change from green to grey. The drop on them is random but wild vegetables are most common, can get other things like eggs too, or just some “garbage”.
-Ah, good to know. Chances are I’ll still run into a couple enemies but this new knowledge should help me a lot. I did know there was some sort of way to get stuff from bushes like that, I just didn’t know how. I thought it might just be a rare chance from 's’mashing them or something. Maybe the was just an older version or I’m being a derp. 
-Side question, is there a way to get milk other than when you first start? I’m very curious. 
-Side mention, I like emojis 
This. This took me a really long time to realize when I broke three limbs.
I imagine ranged weapons (if you can manage to shoot with a freaking broken arm or two) are very useful in events like this. Sadly, Keith only has throwing sticks and an altalt which is useless since actual javelins won’t show up. But seriously, I don’t understand how he is alive.
Get your throwing up to two and you can craft javelins.
If your character has one good arm they can shoot .22 LR rifles ingame.
I am at throwing level three at javelins aren’t showing up, it’s a bug I think. The game says this whenever I first open the crafting menu: “DEBUG: Tried to set invalid ammo of wooden javelin for atlatl”
For killing the occasional straggler without getting hit, throwing sticks are fine, but I’d recommend having a spear for reach attacks and a small chessboard of pits to dance them around. They fall into a pit, get stuck, you stick them with the spear a couple of times, they climb out, you dance away until they get stuck again, wash rinse and repeat.
I usually go for a 5x5 pattern of pits, with the outer ring shallow pits and five deep pits in an X in the middle, because deep pits take a while to dig out.
-It is almost always stragglers, but I’ll still do that just in case. It could be useful even without my arm begin broken too.
-Are you sure about pressing ‘e’ to examine shrubs/bushes? After checking literally over 50 I only got: “This is a shrub. It is empty.” sigh I guess Dahlia root and the rare pot-shot on a pigeon will have to do for now.
(E)xamining shrubs for goods only works in forests and swamps. Grassy areas and towns won’t yield any goods.
Swamps also let you (e)xamine cattails to harvest them, which can be eaten raw, or turned into starch and then flour. The process takes a reasonably-simulated amount of time, but man, I wish I could figure out how to do it faster.
Not sure about the starch but producing flour goes faster with a food processor than a quern. Takes batteries though.
Once I discovered the battery compartment mod you can build with relatively low ranks in electronics, my concerns about battery power went out the window. Stick a full car battery into your food processor and it won’t run out of juice before you do.
But yeah, the starch takes forever. And the food processor still doesn’t work very quickly.
Either way, for waiting for your bones to heal, I think flour is a great way to spend your time.