Moving entire wordpress installation from one website to another

Hello and thank you so much for this help forum. THANK YOU.

I created a wordpress driven website here: https://www.scoutsonline.org/pack790 and it worked great. BUT the Pack wanted their own domain name, so we bought this domain:

https://pack790.org

Once everything was working on scouts online, I backed up all the files on my computer’s hard drive, then uploaded to the new website. It seemed to work great until I deleted the files on Scouts Online. At that point, the site would not function.

I had to re-install the website back to Scouts Online so I could get into the dashboard. Once there I realized that all the permalinks are hardwired and I cannot change them. Even the wp-admin is hardwired to go to scouts online, so when the files were deleted, my hands were tied.

I know this is not ideal, but how do I change those permalinks to point to pack790.org instead of Scouts Online?