How can I concatenate (join) multiple lists into a single list in Python?

Hello everyone, I was working with lists in Python and learning the basics for it, and I wanted to know how can I join two lists into a single one, I am not looking for any specific joining of these lists, in other words, the order of the elements after joining does not matter to me. Please provide me with different methods with example codes for doing this.

What I have:
lst1 = [1, 2, 9]
lst2 = [8, 3, 4]

Desired Output:
[1, 3, 4, 9, 8]