Where to go after the tutorials?

What is the next step in my learning journey? What did you do? Are there some more open ended tutorials that get you doing things yourself?

And for later on, at what point is it worth it to get certified? When, if ever, should I do some partnered courses (https://unity.com/learn/partner-courses)?

 

There is a time for following tutorials and a time for applying them. The next step is making your own game, beginning by something simple and then elaborating on it.

Developing your game will make you face problems you'll have to solve, questions you'll have to find answers to, which the best way to learn.

 

Generally, it's just for when you're applying for jobs that ask you to be certified.

I agree with @APSchmidt : just start working on your own game. I recommend doing a remake of something like an old Atari 2600 game, or else, one of those really simple mobile games like Crossy Road. That way you can create an entire game from beginning-to-end in a relatively short amount of time.

 

Find some tutorials for larger projects, or download example projects and look at how they're structured.
This is something I put off for way too long when I first got into game dev and I regret it.
You need to see how projects are structured properly before making your own game otherwise you'll end up in a gigantic tangled mess.
If you make a really simple game it wont matter so much, but if you're thinking of making anything beyond pong, you're gonna need some structure skills.

 

If you think you're up for bigger stuff:
https://www.youtube.com/channel/UCPXOQq7PWh5OdCwEO60Y8jQ
https://www.youtube.com/channel/UCmtyQOKKmrMVaKuRXz02jbQ