Active basses have a powered preamp that allows you to boost/cut various frequencies ... For instance, Low, Mid, High. Some are more simple and only boost/cut low and high. Some more complex and allow you to shift the point of where the mid frequency is by knob or switch. Passive basses usually have volume and tone control only and in a handful of configurations depending on how many pickups the bass has. Volume and tone. Volume, volume, tone. Volume, pickup blend, tone. These are typical but you'll find all types of cool stuff depending on how much you look.
As far as suggestions and bang for your buck. Do 2 things.
1. Go to a local music store and play a few basses, bro.
you'll find what you like. Try as many as they'll let you play!
2. Spend some cash on lessons as mentioned above.
PS - Welcome to TB!