Like in the picture where can you upload such panels to twitch?
So you don't do them, you usually buy them (https://www.own3d.tv/de/
and on Twitch you can upload the img files, then simply in the settings
I made mine with the panel maker from NerdOrDie
https://nerdordie.com/resources/free-resources/customizable-twitch-panels/#panel-maker
Activate your channel under Info, Edit panels, add image or text panel and upload image.
These are usually image files that you can also design yourself.
Otherwise there are templates or people who personalize it.
And what are the dimensions of the resolution?
300 px in width, but that is what Twitch dictates anyway. There are no limits regarding the pictures, but the panels will have about 50-80 px (estimated). #