I'm not really a pixel artist (though I do have some experience with it), but I think that a Pokemon fan game would probably be a good place to start since the reference material ranges from simple 8-bit and up, with the first few games being very simple, but effective.
Since you haven't posted any examples, I'll just give the advice I'd give to someone who's just told me that they were interested into getting into pixel art and didn't know where to start.
First off; pick a software... I'd recommend "libreSprite", it's based off "Aseprite", with slightly less features, but completely free and has everything you need to get started. For a more powerful option, I'd recommend Krita (which is also capable of animation), but if you specifically want to make pixel art and pixel animations; libreSprite actually makes it easier to use limited palettes and sprite sheets. I actually use a mixture of both for my current game animation setup.
Second; look at how the artists handled limitations when actually using restricted hardware and study them. I'd highly advise The Spriters Resource. If you can think of a well known game for a retro console, you will probably be able to locate a ripped sprite sheet from it.
Other than that; just keep practising and don't be put off if your early work is terrible... it sort of needs to be since the best way to really learn something is to make mistakes, then try and figure out how to correct them.
Best of luck and I look forward to seeing some pixel art! :D