I am on 3 year driving ban will I have to take my test again?

You'll have to resit the test only if the magistrate who sentenced you asked you to redo your test. If there was no condition that you need to resit the driving test before getting back your licence, then you can just request your licence from the DVLA when your ban finished. If you're not sure, then you can always contact DVLA or the court which sentenced you whether or not you need a retake of the driving test.