How to reinstall macOS if can't select items-trackpad issues....

If the wired mouse isn't working either, is your data backed up?

If it is backed up, you can command-option-R run recovery mode to reinstall the OS, and if that fails, command-option-shift-R and use Disk Utility to wipe your Mac. If the mouse does not work in recovery mode, then there is something wrong with the inputs of the Mac, and it needs to be serviced.

If it was just the trackpad, sometimes the batteries can inflate and suddenly trip up the cable that connects the trackpad and keyboard to the logicboard. But seeing as an external mouse you are saying isn't working either, let's make sure it isn't a hardware problem with the USB controller itself on the logicboard.

It means your Mac came with Big Sur. You could if you want use Disk Utility in the installer to reformat the drive (erase the content, and reinstall Big Sur). Big Sur will not install on top of Monterey or Ventura, but once BIg Sur is installed you can upgrade back to them before recovering your backup. That may explain why you can't select anything to install, is nothing to do with your mouse, but everything to do with their being a newer system on board.

Once you have reformatted and reinstalled, if you the mouse still fails to work, then you know it definitely is a hardware problem.

If you can reformat, but not reinstall, and your Mac is clearly connected to the internet to a secure WiFi or ethernet line on the installer, then I would say there could be a hardware problem and you need to take it in for service.

Can you get/use a wired USB mouse?