Advanced concept: each of these methods accepts the string itself as the first argument of the method. However, they also could receive additional arguments, that are passed inside the parentheses.
No professional has all the methods memorized, you always refer to the documentation. Documentation on string methods https://docs.python.org/3/library/stdtypes.html#string-methods
Documentation on the format syntax #https://docs.python.org/3.6/library/string.html#format-string-syntax