Congrats on working through the Fundamentals courses!

I encourage you to pick whichever style course gives you the most motivation to keep practicing.  As long as you are a GT member you'll have access to all the courses in the future.  So, you can always start working on another course later, or even at the same time!

With that in mind, jazz material is going to be a little bit more advanced, so you might consider working through the blues courses first.  That will put you in a better position to work on jazz because there are a lot of blues elements in the foundation of jazz.

Further, a great deal of rock was also based on blues elements.  So it would also help getting further into rock.

And while you are working on all that, you could work through the standalone material on jazz chords.  For example:

https://www.guitartricks.com/tutorial/1166/

Or this collection of tutorials on improvisation will help you get working on the required skills & ideas as applied to any style.

https://www.guitartricks.com/collection/learning-to-improvise

Hope that helps!