Hello Maxime, welcome to the Microsoft community, I'll be happy to help you today;
I understand that you want to center the window using Borderless gaming;
To center a windowed game: simply use the game (don't alt+tab out of it) and press the Windows key+Up Arrow on your keyboard and this will force the window to use the "full space" of the current monitor. it will still be windowed just centered and filled as much screen space as it can.
To make the game full screen, just press Alt + Enter while using the game. the same key command will also return the game to windowed mode at any time. (I don't think Destiny 2 really likes being Alt+Tabbed when it's full screen, so I open the window when interacting with my second screen or other apps like discord);
Source:https://steamcommunity.com/app/1085660/discussi...
Hope this helps, see you soon!