My first build

Hello all, I'm planning my first build ever and I was wondering if anyone could help me since I am not that known with all the parts yet,I want to build a pc for mainly gaming and light designing and modding

So I can salvage 1 120gb ssd and 1 tb hdd from my laptop so don't need those, I would like a full tower with upgrade options.

I would like to spend around 600-800 euros( I live in the Netherlands) I just want to start getting a little more serious and go desktop again so I need enough upgrade options because I can't spend that much when I will build it at first.

So between 600-800 euros for a system 

Any help will be appreciated



Do you need a monitor, operating system, keyboard, mouse, speakers, etc.?  Or is it just the hardware?