You can learn Julia by MIT lecture and the resources on the website:
https://ocw.mit.edu/courses/mathematics/18-s190-introduction-to-computational-thinking-with-julia-with-applications-to-modeling-the-covid-19-pandemic-spring-2020/syllabus/
https://julialang.org/learning/
https://docs.julialang.org/en/v1/
"Because Julia's compiler is different from the interpreters used for languages like Python or R, you may find that Julia's performance is unintuitive at first. If you find that something is slow, we highly recommend reading through the Performance Tips section before trying anything else. Once you understand how Julia works, it's easy to write code that's nearly as fast as C."