I had a problem ...

What problem?

... and deleted thunderbird.

Please explain in more detail what you did. Unless you also deleted the Thunderbird profile, you don't need to set up any account(s) again after re-installing. Thunderbird should just pick up the existing profile.

I had a problem and deleted thunderbird. Now I have reinstalled and cant get to the allow button for account setup. It seems to be way down the page and I cant sroll down to get to it.

Some programs don't always fit well on a small screen, like a laptop's. Fortunately, the content of most Thunderbird windows can be shrunk with the same keystrokes you can use to shrink a web page content. You can temporarily shrink it until the button is accessible.

<Crtl+plus> to enlarge <Ctrl+minus> to shrink <Ctrl+0> to return to default size

"cant get to the allow button for account setup" sounds like you are at the oauth2 authentication dialog box.

Correct?