I got hacked and I’m not smart enough to fix my blog

Please help! Yesterday my host pulled down my entire account because some rogue script was running on my account. Apparantly someone hacked in via my WP blog and wreaked various havoc.

I’m trying to get things up and running again as quickly as possible. So! I downloaded a fresh installation from wordpresss.org, uploaded it and tried to run the install thingy. It tells me that WP is already installed, and that I need to clear my db tables to re-install.

Question 1. How in heck do I clear my tables without losing everything? No, I don’t know how to back up the database. Yes, I’m dumb.

Question 2. When I go to my site now, a few blog entries show up. But all of the links go to 404s. Why? When I try to get to my admin page, I get a 404. If I go to https://www.electricboogaloo.net/wordpress/wp-admin/index.php it says: “Your database is out-of-date. Click here to upgrade it.”

Am I wrong to be suspicious of that message? Is this page a legit WP deal?
https://www.electricboogaloo.net/wordpress/wp-admin/upgrade.php

How is WP going to upgrade my database?

Question 3. I’m an artist, not a programmer. On a mac. Should I kill myself now you think?

Question 4. HOW MUCH DOES THIS SUCK?

Thank you so much for any advice you can offer!
Tiffany