Help with setting stream

[[6S] Jacob]

Hello guys,
i need some advice and help to get my stream ugrade in quality section.

I spent few days by finding tutorial videos on Youtube to set all things up but in my matter language there is no helpful video and videos in english on this topic are really dificult for me to understand.

What i need to help with:
I need to set the best possible quality acording to my setu (i know i should be testing it myself, but i don´t understand anything in this theme - jokes as "then don´t do this" won´t help here).

i7-6700K 4 GHz
GTX 970 4 Gb
16 Gb ram 2133 Mhz
connection upload: 65 Mbps (i found it is 65 000 Kbps so i can use high Bitrate - i have also read twitch TV allows max 3000 Bitrate)
Monitor resolution: 1920 - 1080
streaming program - OBS
i don´t use any special encoder - using CPU encoder x264



If you guys can help me in this case to set the best possible quality, i would be realllllllllllllly glad!

I have already tried 720p and 540p in 30 and 60 FPS with 2000 Bitrate - i have read it is universal for tests. Also in chat i was told the quality still sucks.