If I practice soccer every day, will my skill improve?
Yes, as long as you are using good form.
If you are practicing with bad form, your skill will decrease because you will only be reinforcing the mistakes you are making. If you are practicing with good form, then yes, your skill will absolutely improve.
However, I would recommend taking at least one day a week off to give your body a chance to rest. Your practices will be more effective if your body is rested beforehand.
Also, it’s important to know that while your skill will increase with practice using good form, you may not actually notice or feel a change for weeks or more.