upgrade gone wrong, please help!

I have lost my wordpress. I use itheme2 and upgraded to the new wordpress upgrade.

I installed the theme and it worked fine, I then installed the upgrade and it logged me out of the dashboard and I went to log in again and the page is there to log in but upon doing so, my dashboard is gone!

My holding page has also gone too, when you go to https://www.supersavvysteph.com it is just a blank white screen.

My boyf. did some searching of help files here and then removed the itheme2 folder so it would default to original settings, it has not done that at all.He couldn’t fix it.

He said the files are still all there (he can see them using FTP) but nothing is showing up on my webpage.

I’m pretty new to this after going self hosted from blogger so please explain things in simple terms, any help you can give would be fab ??

Thanks