Yes
if they did login then you’d store the “telegram session” in the session so when they leave the site to twitch auth and come back yo ucan recal it.
Since you can’t/don’t login with telegram
Then you either ask for the telegram ID before Twitch Auth and store it in session.
Or they Twitch Auth and then you ask for the telegram ID. Which probably wouldn’t need a session.
In both cases you don’t to send the data with/via Twitch to come back to you.
You either store it locally in session (or localstorage or a cookie or something).
Or you ask for it after Twitch Auth