This depends entirely on your current skill level & understanding of the music.

In one sense, you are right: there is no other way to learn to play some given piece of music without knuckling down & doing the repetitious practice that the piece requires to learn it.

But if a piece is well beyond your current skill level, then it might be more productive to work on some basic lead skills (playing single note lines, practicing scale patterns & techniques like bending, legato, etc.) that are used in most rock solos.  Then as you gradually build your skills try some of the solos you want to play.  

Either way it's a whole lot of repetitious practice until those physical motions become second nature.

 So what is your current skill level?  Are there solos you can already play?  Some you are working on but can't yet?

You could just work through the Rock course doing all the lead guitar material.  Look for everything that shows the skills you need to play solos.  I also have a lot of tutorials on building those skills.  For example.

https://www.guitartricks.com/tutorial/914/

https://www.guitartricks.com/tutorial/1614/

Hope that helps!