i forgot my screen password

You can reset the phone without a computer, if you follow the steps in this article:

How to remove your iPhone, iPad, or iPod touch passcode without a computer - Apple Support

In case this does not work, you'll have to use your computer to erase the phone and set it up again:

If you forgot your iPhone passcode - Apple Support

Screen Time password?

If using IOS 13.4 or later or Catalina 10.15.4 or later, see the Apple Support article(s) below. Link to contact Apple Support at the end of the article.

Screen Time passcode reset.   *

ASC YouTube for how to reset your Screen Time passcode on iPhone, iPad, and iPod touch — Apple Support

If necessary,  you will need to restore the device to factory settings. Do not restore from a backup made when the Screen Time code was active.

Restore to Factory setting.      *