Building my first server

[MmeCromatique]

Budget (including currency): 1000€ 

Country: France 

Games, programs or workloads that it will be used for: Minecraft server always running with 10 people but up to 50 or more. 

Other details (existing parts lists, whether any peripherals are needed, what you're upgrading from, when you're going to buy, what resolution and refresh rate you want to play at, etc): I'm completely new to server building but already have repurpused old laptops or Pi, I don't really know what I need, I think of buying an i5 10400, but no idea of what MB or PSU to use, even memory except knowing I want 16 or 32Gb of RAM depending on the budget left and at leat a Tb of storage. Also, should I use a regular desktop case or a server rack? I'd like to buy as soon as possible and well adviced if possible on a website like https://www.topachat.com/ or at least in western Europe.