Here are some YouTube playlists of table tennis that I found useful as a beginner:
My favourite English Channel is PingSkills. It is very beginner-friendly and explains table tennis techniques and rules in a simple and clear way.
全民学乒乓 横拍篇(Table Tennis for Beginners – Shake-Hands)
全民学乒乓 直拍篇(Table Tennis for Beginners – Penhold)
My favourite Mandarin Channel is yunpeng guo’s channel. Guo is the founder of pingpangwang.com and he creates various comprehensive videos for different levels of players. He explains table tennis techniques in great details and he is very spot-on when pointing out the common issues of beginners.
Here are some tutorials from table tennis world champions with English Subs: