You are slightly in the wrong place - but never mind. Soup is idiot proof. Presumably you want to make it low carb. Chop your veg - whatever you fancy - into dice sized pieces. For example, onion, carrot, celeriac (the roundish celery tasting root). Mushrooms with leeks and cream is good. Melt some butter in saucepan, mix in chopped veg, heat in butter for a while then add some stock. (I like Kallo organic stock cubes which is sold in uk supermarkets.) About 1 cube for each 500ml. Cook until a knife goes into veg easily.
If you want a smooth creamy soup you need a hand blender (between £10-25). Seasoning up to your taste, but wait until last minute before tasting for salt. Some cream added at the end is good. (If you add it earlier it could boil over).
Chicken soup- stock, finely chop a carrot, some celery stick, whatever veg and herbs you fancy- sliced cabbage works, also small broccoli florets. Boil about 15 mins. Add some cooked chicken (you can buy a cooked piece of chicken or in another pot cover a chicken breast with water and gently cook until no longer soft -15-20 mins. Cut it up and add to soup. Be sure to heat any meat through very thoroughly. Sometimes a squeeze of lemon juice is good for chicken soup.
Once you know how to make a basic soup, it’s easy to improvise. Frozen herbs add some more flavour.