So, here is a simple recipe for a basic vegetable soup:
What you need for 2-3 persons:
2-3 potatoes (One for each person)
about 1/4th celery
spices (salt, pepper, parsley)
optional: (broccoli, cauliflower, more carrots or potatoes, for whatever kind of soup you want to have....)
Cut everything into rather small pieces, fill them all into a pot, add water so that close to everything is "drowned". Let it cook until everything is soft. You can puree it or not, depending on what you like. And voila, the soup is ready! If you puree it, you can as well add a bit of creme fraich or cream at the end. What I personally like to do, is to add a bit of chilly, but that's not for everyone.
Simple indeed, right? Easy as pie! (maybe I should make one again....)
Now, if you want to make a broth only, you should only use the celery, carrots and leek, those are the typical and most basic ingredients. You have to let it cook for much longer, but eventually it should turn into a nice vegetable broth.
But I leave that up for your own tries!