Hi! If you go through some of the older threads on here I think you‘ll find that loose lead walking is probably one of the most discussed problem and I think the vast majority of us have battled with it at some point, - that‘s not intended to discourage you but more to reassure you that you‘re really not on your own!
There are lots of methods from keep changing direction, to keep stopping as soon as the lead goes tight and then waiting until the dog turns back to you and continuing when the lead is loose again, which is the method which I favored but you‘ll probably find loads of others online.
The breakthrough point for me was learning to relax and accepting that Humphrey (who is now 5) was probably never going to walk perfectly on the lead in all situations, cockers are ruled by their noses and any distraction is very difficult for them to overcome. Unfortunately it took a long time for the penny to drop for me but once I took the pressure off myself and my dog things started to improve. My advice is therefore to pick a method which suits you best and stick to it, keep training sessions short (its very hard work for your dog) and be generous with praise and encouragement, be consistent but patient and be prepared to continue the training permanently. Above all, don‘t get frustrated because other dogs walk better than yours , they‘re probably not cockers!
Best of luck, you’ll get there, - eventually!