Can't open/install Photoshop v21.2 or older. No administrative access to the program folder.

I tried to update my Photoshop recently but now I can't open it. I read this error and tried to access the Adobe Photoshop 2020 folder but I don't have administrative access to it (although I am the admin for my PC). Therefore, I can't delete or move the folder that's conflicting with the update. I also tried uninstalling Photoshop but the files are still in my drive. Any ideas on how to fix this? I'd really appreciate it.