[Question] Using a mini-keyboard/synthesizer/oscillator, etc?

I'd like to start using something to basically fill in the lack of band I have (bass and percussion's missing) as well as experiment with some new sounds. That said, I have no idea where to start. I've looked at things like the Akai MPK Mini II ($100) as well as the Arturia Microbrute ($300) and like them because they have "effects" as well as a keyboard, but I don't really know the differences between them, and one costs 3x the other. So is there anywhere I could find some beginner information that I could apply to what my wants/needs are with this equipment? Also, is it going to be a huge problem that I only use a chromebook? Will I need to find a PC/Mac with an operating system to use these things? Thanks!