Hi. You don’t have to drink it every day - it is up to you how often you want to use it and for what meals. Personally, I have Huel (or a similar product, like Soylent - the industry leader - or Jimmy Joy) pretty much every day for lunch.
It could help you lose weight, if that is what you want to do. If you look around at the instant food forums, you will see that a lot of people have had success losing weight with these products. But there is nothing magical about them - they are just good, healthy food that is easy and inexpensive to prepare. Probably consuming Huel before exercising won’t make much of a difference.
A couple of pointers - you can play around with it, try having it different ways. Add flavors, spices, sugars. Use a blender or not. Personally I like plain Huel by itself, but I also like the savory recipe that is written on the insert (adding vegetable broth). You can put in a blender with a banana. Have some fun with it and see what works for you.
Just remember don’t drink it fast because that can upset your stomach - it is not a soft drink.