I would suggest dndbeyond.com then at the top Game Rules -> Classes -> Pick a class. On the left side of the screen for the class you choose is a index, click the "Creating a ClassName" and under that you'll see something like "The ClassName Table." Click that to jump there and that should give you a general idea and let you explore further.
Keep in mind:
- There are a few things that are purposely changed
- There are bugs (like sneak attack damage for Rogue is suppose to increase over time, and currently doesn't in EA)
- There are many missing classes and class specializations that you can't choose yet. And furthermore ignore anything tagged (UA)
- Level 4 is the cap in EA right now.