There is also the thing that cars use DC voltage, and a house is AC.
But a car engine alternator isn’t the right type of power so that’s a flat out issue there.
A wiring panel would need to have a proper hook up to take the power and put it into the panel. This is not standard and would take a very experienced electrician to do it right to make sure you didn’t have issues. I can think of any number of them.
The typical kind you get at the store isn’t going to provide enough power, average house is 200+AMP service or so in the US. Depending on size. The Home Depot/etc generator usually has a few plugs you can then plug some items into.
Then who is going to install it? It’s a jury rig job. Service panels are not designed with this type of hook up. You might be able to do it, but it would require a huge generator. 20 amp service can handle a 1500W microwave. $200-300 generator gives about 3000W after startup which is 50% load they run at. There’s usually 4 plugs for the 20 amp. One big one for like a welder or dryer.
my father is a Master Electrician for 30ish years. I helped him for many summers, weekends, in my early teens into 20’s. I’ve pulled more wire and hooked up more devices (plugs/lights/switches, fans etc) than I ever care to again. You have to know what you are doing messing with an electrical panel or there’s going to be major issues. The wrong gauge wire causes problems, improperly connected plugs/switches. Wire being niched, or the hole in the stud the wire goes thru is too close to the sheetrock side and a screw hits it. (within 1 1/2" you need to protect with a metal plate, or a sheetrock screw could intercept the wire. If the load line isn’t tightened enough in the panel the panel can get hot and that’ll start to melt the wires… I’ve seen that melted mess… fun 3 days re-wiring a whole panel and running more home runs thru an existing house due to melted wires) It didn’t start a fire… just got hot enough to almost do it. That person was soooo lucky. Basically the electrician didn’t tighten a lot of it down enough. My father thought it was prob a new journeyman and the master electrician didn’t double check the work enough. House wasn’t more than six months old. We only ripped up a walls to get stuff pulled, luckily most of it was run thru the attic.
Electrical codes are a bitch, but there for a good reason. Bad wiring causes fires.