Build: In my eyes, effort wasn't put into the build. It barely even looks like a nether fortress. It's just some floating jumps with a nether brick rectangle in the middle. Your build needs to portray your theme accurately so that there's cohesion between the two while also making it attractive. I didn't see that in this build.
Parkour: The parkour is way way way too easy and short for the easy difficulty. We want easies to be a little harder than this and to reach 20-40 jumps. Furthermore, the parkour was incredibly linear as you utilized the same jump (and blocks, most of the time). It was just 1b's and 2b's. There was no variety. You need to be more creative when building parkour so that it's enjoyable to do.
I hope you take these criticisms into consideration when submitting maps in the future, good luck!