Improving my understanding of functions and methods

[menator01]

I'm taking some advice from one of the tips here and using pylint and pylint3.
I'm using it on the code I posted in the review. I got the original code only throwing to warnings about(too many instances) which I am working on now.
On some of the code for my methods says could be a function. If I put self in front it, it goes away. Using the code I posted, it should be safe to day for the header image and the footer I could choose to put those as functions in the top of my program. They never change. For data manipulation those should be methods. Example I can use methods to pull the titles out and display. The same for the information that the titles display when clicked.

Just need input best practices most used. A lot of code I've seen seems to be what the author favors.

On a side note, I've noticed pylint/pylint3 throws warnings if too many methods are in a class. Is this also a preference? Whether it be one or 100? I know a class creates an object and methods describe what the object look like so to speak. Say the class creates person and the methods give that person brown hair, height, build, and so forth. Well anyway any input would be great.

Thanks