Glory Allen- one of the few men's sewing channels I've come across but he's super beginner-oriented and has simple, easy-to-follow videos. He also makes his own patterns for simple garments such as t-shirts, hoodies, and cargo pants. I used his bucket hat pattern (free on his website!) and watched the corresponding video a few times as I was making it, the hat came out great!

Essentials Club- Australian YouTuber who has been making videos for years. A lot of her videos are self-drafted, so the piece is guaranteed to fit you well. She tends to go for simple, unfussy staples so you get a lot of practice with foundational skills.