Are there any ways you can prove to people witchcraft works and it isn’t a scam?

I have been practicing since I was very young, but I never do spells for anybody else except a few protection spells in times of need/health. I am open about my practice, i don’t say much but I think they just know (i have a practice room).

Recently someone came up to me asking me how do I know it’s real, and if I can do any magic that can prove it’s real (that works instantly or in a few days). I was wondering what other witches do? I am curious if there are spells I can do that will prove the authenticity because I am sure not everybody feels the energy I do. People around me are curious (no bad intentions though) and I wanna help their curiosity.