Board Game Arena

Is there a way to ad AI opponents to games like Euchre I'm trying to teach to a friend?

Plenty of 2-player games, but some of of the better ones require more players -- and I haven't been able to get others to join, so I'm stuck.

There are no automatic AI opponents to step in on BGA. Some AIs have been built for specific games at various points. There was recently (just a few threads beneath yours) a discussion about the possibility of LLM players: https://boardgamearena.com/forum/viewtopic.php?t=48652