where do I go to take my python from 10/20 lines of code to creating larger and more advanced programs?

Answer 1

Don't think about the length of your code, think about what it's supposed to do!

The code gets as long as it gets, and if it works, who cares about how many lines it has.

Usually, if you do your job well, it will even be shorter than if you do it less well.

As you proceed from one project to the next, quite naturally some of them will become longer.

Answer 2

Try to solve challenges posted on SoloLearn on your own.
Study popular python codes posted on the code playground and try to analyse them and learn from them.
Read the standard documentation of Python and get familiar with libraries like functools, itertools, numpy.