There are a few good tutorials on Udemy but they are not free.
The free one you can checkout is this one: React Native for Absolute Beginners - Udemy .
The best among all: React Native for Beginners
But probably the best way to learn react native is Facebook documentation itself. It is one of the best documentation I have ever seen. Just start with the quick tutorial and try to build something yourself.
I visited these tutorials which are shared above and I don’t find any interesting one in it, so please share the proper tutorial as I want to learn it.