dara chan

Hello I moved to the UK since end of July 2021. As a housewife , I do not have work , my saving interest less than GBP1000. My friend just told me everyone needs a UTR number even no work and income. Do I need to register UTR number? My husband submitted Self-assessment form but do not know how to use marriage allowance from me, do I need a UTR for him ? Appreciated all your feedback.