Hi I'm super new to bitsy and anything coding related in general so sorry if this seems super obvious but I can't seem to find anything so far that has helped me!

I'm trying to combine two bitsy sections into one game (and will continue to add on to it). From my understanding it can be done, I'm mainly using Cecile Richard's stuff as a reference point and they have what I believe is different bitsy games as the avatar changes, for example from person, to cursors, or to invisible to just have visual animations and stuff. I'm not really sure how they've done it and would love some help though in very basic instructions! 

I've attempted to use bitsy merge but I don't think I'm using it correctly as once as I get to the end of one bitsy portion it just freezes up.  Would love some help or some directions to good videos or how to's if you know any, thank you!

I am not sure about merging two games, but the current version of bitsy supports changing the avatar between rooms within a single game. Aside from your main avatar, you can designate any sprite you have made to be the avatar for a particular room by clicking on the avatar option at the bottom of the room editor (scroll down in the room editor window if the button isn't visible). Especially if you're new to coding and bitsy, I recommend using the built-in tool first because it's very simple and doesn't require digging into the code.

as almostabetrayal says it all depends on your goals 

if you just want to change the avatar sprite, the built in features will probably work

another possibility is the bitsy museum hack, which was discussed in another thread recently: https://itch.io/t/2762533/does-the-bitsy-museum-hack-still-work

good luck!