I always point people towards Shaun Spalding and this video seems to be the most up-to-date for learning how to make a platformer
however as mentioned in the video, there are other videos on that channel which may be more suited towards beginners.
I make tutorials myself but haven't covered this topic. I would like to in the future so maybe subscribe https://www.youtube.com/channel/UCBmOLRTaPrfOxnTqpCLrwdQ and I will probably get around to it