Blog is missing completely

So I’ve read through over 20 of similar posts but I seem to be different because I can’t pull up anything AT All after trying to update my wordpress. My site is https://www.leahmossphotography.com/blog and I’ve tried https://www.leahmossphotography.com/blog/wp-login.php and I can’t get in at all. Thankfully I did do a backup before I tried the upgrade, but it was saved as a GZ file and not sure what to do with it because I can’t even get onto the site at all. If someone could “dumb down” an answer for me I’d greatly appreciate it!!! Help!!!!!