Find out Twitch's name without knowing him😂🔥?

I have a friend and the stream on twitch, now to my question, can I somehow find out his name without knowing his name? He wants me to find out for myself, but I don't know how 😐🔥 can you help me in any way?

May be based on other nicknames that he may have on steam or other platforms, he may have the same or similar on twitch.
Otherwise not

I've already tried it