Getting your hands on free gear is awesome. But you're going to need to add a lot more things to make them useful. My first thought is that you should get a better understanding of how basic modular modules work. There's a free eurorack simulator known as VCV rack. There's a virtual version of Clouds and Braids in it. You will also find a lot of other modules like VCAs, envelope generators, etc.
Learn how to build a basic set-up in VCV first. It costs nothing so you can make as many mistakes as you like and experiment recklessly. Get a good understanding of how it works and you'll find that making decisions on which pieces of kit to add to be a lot less daunting.