How To Hide HUD Counter-Strike 2

1. Open your console.
2. In the input field write:
   cl_draw_only_deathnotices 1
   
   If you want to show the HUD again input:
   cl_draw_only_deathnotices 0

You can also use another command, if you also want to hide the crosshair but the you need to Enable Sv_cheats.
cl_drawhud 0
and to show again
cl_drawhud 1