Welcome to the Forum!
Because of the Monitor Issue: When You go to Settings>Displays, You have there the Options ''Join'' and ''Mirror''. Set it to Join and make a Screenshot of the Monitor Layout and post it here please.
Because of the Game: Do You use Steam for it? If yes, use the APT Package or download the .deb File from Steam directly:
And then simply try the Game.
For Your Software: Brave comes preinstalled on Zorin. So, this should be fine. Vivaldi offers a .deb Version for download which adds during the Installation the Vivaldi Repo. So, You will get Updates for it, too. You don't have to manually download new Versions. So, that should be fine, too. VS Code offers a .deb Version on their Website, too.
For Notepad ... You could check the preinstalled Text Editor. It is simple. Alternatives could be Kate or KWrite.
For Outlook would be Thunderbird an Alternative. But because of Your Descirption of Your Use Case, I'm not sure if this will work this Way.
Photoshop and Linux ... are not good Friends. You could try to get it to run with Winboat or Bottles but from what I've heard it doesn't seem to work. DaVinci Resolve is not easy, too. You could take a Look ath his Guide: