If i want to get on my website, I get "403 Forbidden"

Everytime i want to get on my website i get "403 Forbidden / You don't have permission to access / on this server." How can i disable this to edit the website?

I've tried to change the php settings from FPM to FastCGI. To whitelist *. To Disable the "smart static files processing". To use other Browsers and Devices.