Unfortunately, trignomotry is a must for implementing odometry and pure pursuit, even some move to reference pose/point algorithms. I would recommend looking into that first.
I’ll link two more pure pursuit resource:
I used python and the smoothing algorithm they cited to create smooth paths:
If you want to look more into path tracking, this article is very helpful (it requires a lot of math, but if you are really interested in the topic, I would recommend reading it in the future):