404 first devjob not found.. :-(

This is a question with a bit of backstory. Bear with me.
Firstly, i’m back (again😂) now pursuing my software engineer goal at a university.

I had a group project course this spring and me and my group produced a kinda half assed product that could help within sports teams, for a customer at the university (won’t go into details). After the course ended I couldn’t go home to northern Sweden and stayed in my student accomodation for the summer. So I took the chance and offered myself to continue work on the product this summer to make it more usable and functionable, and they hired me (first real devjob!🥰)! Now when I look into the parts of the code that I did not write (our team communcation were bad), I realize I don’t understand fully how it works and therefore feel it’s better for me (also to learn more) to rewrite some parts my old group produced, and to actually make it easier to improve. Now finally the question; how do you feel about taking on a product, scraping some parts to rewrite them, and (in your perspective), improve them?