Can I linked my acc without changing my avatar?
And if doing it through twitch, do I need to change my username to the one which is written in the instructions?
I can do it only in 2 months, can u do it manually?
You can link via twitch, yes. You just need to make sure your Twitch display name matches your Twitch username. You do not need to use the username shown on the guide.
I did that, but it still refers to my old twitch name