if the autopilot is engaged, you can’t physically move the wheels, because it is moving them for you.

I'm pretty sure on newer 737s the autopilot disconnects when it detects a sufficient physical force on the yoke. But yeah the button is easier and safer.

most important: the switch for the “fasten seatbelt” sign is usually on the bottom of the top panel. You can flip it on and off as much as you want. (Older planes will also let you do this with the “no smoking” sign).

Gee, how the hell did everyone miss this? The most important control element.