Here are some of my favourites:
Pixel Overload is a really good pixel art-based youtube channel https://www.youtube.com/@PixelOverloadChannel/videos
Reece Geofroy has some great pixel art tutorials. https://www.youtube.com/@ReeceGeofroy
Also this video my Goodgis is a must-watch for all new game devs.
Hope these were helpful. Good luck with your future projects! :D