Why is there is no setting for passwords and accounts on iphone 8

iOS 14 no longer has Passwords & Accounts. The information has been rearranged. You may still do what you're trying to do; however, we have no idea what that might be.

Things do move and change as software versions progress.

It hasn’t been removed. Why would it be? It’s just been changed around a bit. You know that Settings has a search facility? But if you explain what you’re actually trying to do someone might be able to help.

The answer depends completely on the specific account and what it’s used for.

Here’s an example. If you’re using a gmail account for Mail, the answer is:

Settings > Mail > Accounts > Gmail > Account > SMTP > Gmail SMTP Server > (Username & Password go here)

“Accounts” ... for what?

For Mail? Settings > Mail > Accounts.

OK. Enjoy.