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Yes, of course.

Make sure you have kept copies of your backup archives in more than one places. I usually recommend one copy on your server, one on your desktop (or, generally, on your computer) and one in a USB flash drive. The idea is to better be safe than sorry.

Then, upload the backup archive and Kicsktart to your site.

If you can't access Kickstart: Delete the .htaccess file on your site. Go to your hosting control panel and choose PHP 8.1 or later – that's what Joomla 5 needs, the restoration could even work with less. Then retry running Kickstart.

Use Kickstart to extract the backup archive. Then click on Run The Installer to launch the restoration script. It should propose you the same connection information your site had at backup time which, presumably, is the same still. So, it becomes a matter of clicking Next until the restoration is done.

Finally, close the tab with the restoration script and go back to Kickstart. Click on Clean Up and your site should be back to its previous state.

If this didn't result in a functioning site, delete all files and folders from your site and repeat the entire process. The reason is that extracting a backup archive does not delete files, it only creates missing files and replaces existing files. If you have mixed files from different Joomla or extension versions you might still have a broken site. Removing everything before the restoration will, of course, address this possibility.