Unlike vanilla, you can only wear one item with tag “BACKPACK”, which in turn corresponds to “B” shortcut in advanced inventory for quick access. Which is similar to how boots or helmets are handled in vanilla - you can also wear only one.
You can wear other stuff like briefcase for example, but for accessing that, you have to pres “W” for worn items, select row with desired container, and press “C” to drill into it.
If you meant wielding multiple containers, you can’t. Just like you can’t wield multiple kanatas or multiple anything, really.
On the other hand, if you want to move large volume of items and have strength to do it, you can wield a steel drum and have all its 200 L to your disposal.