MiniZinc is high-level modeling language, before using it I'd suggest taking course https://www.coursera.org/learn/discrete-optimization where you could use/create different solvers.

Only after it makes sense to take https://www.coursera.org/learn/basic-modeling and https://www.coursera.org/learn/advanced-modeling courses.

If you want a quick start read really good tutorial on official website https://www.minizinc.org/doc-2.7.2/en/part_2_tutorial.html and play with examples at online playground https://play.disopt.com/ or locally installing MiniZincIDE.