Can't join a server or "play" in fullscreen mode

Hello guys
When I start FiveReborn it starts allways in windowed mode and when I put it in fullscreen mode with ALT+Enter I get a blackscreen and nothing happens.
When I don’t put the game in fullscreen mode and join a server I guess I could wait 2000 years and its still loading.
I also get some purple stripes sometimes that are flicking over my application.
But sometimes when I wait 10 minutes I can see the chat for some seconds and than again nothing and the loading circle stucks …

I downloaded all the plugins, the trainer and stuff like that I reinstalled GTA V and FiveReborn (it took me 2 days to download GTA V). I installed visual C++ 2015 and my drivers are all up to date.
I just want to drift -.-

ohyeah and here the rest:

GTA V version? the latest O_o 1.35 I guess
Up to date? Yes
Legit or Pirate copy? Legit
Steam/CD/Social Club? Social Club
Error screenshot N/A
GTA V folder screenshot
FiveReborn client folder screenshot

Please contact their server owners. They are on Discord.

Disable TeamViewer or any smilar program. If you don’t have it then on tray icon exit all programs except default ones. Also update your graphic drivers and/or reinstall them

Please update your GTA V latest version is 1.0.791.2