Battery, charge limit

You cannot directly. You can go into System Settings ➜ Battery, and click on the ( i ) icon next to Battery Health, and then turn on Optimize Battery charging. It will detect and learn your usage and eventually stop charging at 80% while connected to power while it knows you don't normally need to use it, and will charge up to 100% before you need to take it off of power so its ready when you need to leave.

Outside of that, it cannot be forced, and you should not worry about it. The Mac can manage its own charging, it cannot be overcharged and no damage will come to the battery.

Rodorg wrote:

I'm just currently only using my macbook at home at the moment and it's more convenient to have it connected to the charger all the time, but from what I've heard, keeping the battery at 100% for a long time is harmful

It is not harmful.

On the Internet, I saw there are programs that keep the MacBook charged by 80%, but they only fit intel processors, not m1

It is not necessary on M1 Macs.