First time GM Assitance

So, I've played various TTRPGs on and off over the years. Recently, my little brother (he's 31, I'm 46) has been our GM and he's been doing games in Foundry. He kinda mentioned maybe ME being the GM for the next campaign. I've never done it before, but I'm on board.

I figure I can keep using Foundry (we're not all local), but I should probably start with a one shot. Any recommendations for a one shot I could try to GM first that's supported in Foundry?

We've already done Sundered Waves and Mark of the Mantis... so maybe a different one.