My friend does not believe it’s possible for Imams to perform miracles as they believe only prophets can perform miracles. Is there any proof that the Imams were given the ability of performing miracles as well?

Tell them that in Sura Naml verse 40, the one who had some knowledge of the book, who was not a prophet, performed the miracle of teleporting the throne of Sheba from Yemen to Palestine. Asif ibn Barkhiya had some knowledge or the book and he was able to achieve that. The Imams have been given the full knowledge of the book, so they are able to perform miracles with the permission of Allah.