Android 11: Needing to restart every 5 to 7 minutes because of browser freeze. Battery lasts under

[user4E7ordadrW]

Hello,

Two issues:

1)  After waiting 2+ weeks for my phone to optimize the applications, my battery is lasting less than 24 hours.  Under Android 10, it lasted 2.5 to 3.5 days!

2) Whether I use the Samsung Internet browser or the included Chrome browser, I can get them only to work for 5 to 7 minutes before they freeze.  I tried clearing the cache and data.  Even if I stop and resart either browser, the tabs stay frozen.

How do I go back to Android 10 on an UNLOCKED Note 20 Ultra 5G?

Thank you.

[user4E7ordadrW]

The phone keeps coming up with a message about a program taking a lot of CPU and killing the battery. The app is:

com.google.android.gms.persistent

Why does this app exist?
Why is it taking so much CPU and battery?

Why does it keep coming back even after I answer close the app the the message?

How do I remove it?

How do I go back to Android 10?