OnePlus 11 issues - HELP!

Okay, I just got this phone a week ago. I'm having some weird issues. When watching tv on apps (Netflix and HBO are what I've used so far), if I press the volume button it changes the screen color for a second. It changes back but it's weird. Anyone know anything about this?

It will just randomly turn speaker phone off when I'm in a call? Is this a setting I can change?

Also, if I'm holding the phone to my face while talking on the phone it will sometimes press buttons and hang up. Can I change this?? Super annoying.

Sometimes the whole screen just stops responding to my touch? Like it's almost like it's waiting to catch up to what I want it to do. Never experienced this on any phone before.