How can I reconnect Gmail accounts to Apple Mail app?

I recently updated my gmail account password as I was alerted that it had appeared in a data leak. Now I can't get mail on my iPhone, iPad, or mac laptop. I have tried everything suggested online. Help!

I was informed in my passkey that one of my gmail accounts password was detected in a data leak. I updated it and after I couldn't get that account to come in on my iPhone. It still worked on my iPad. I tried different approaches but nothing worked. After fiddling with it I power cycled my phone and then it worked.

I have a second gmail account that I decided to update since it was also apparently compromised. Because my google online account doesn't seem to be able to show me anything but the original account I ended up updating that password again. Afterwards my original email account stopped showing up on all my devices. I downloaded the gmail app and it is there but I want to get it back on my mail accounts on my apple devices.

I have looked up online so many fixes but they either don't work or I can't find where those account settings are. Help!

[Edited by Moderator]