Please follow these simple steps to create a UPI ID:
Open a third-party UPI App (such as GooglePay, PhonePe, etc).
Select the Add Bank Account option (it may be at different places in different apps).
Select SBM Bank India Limited (or SBM) as the bank account.
Follow the steps given on the app (you may need to enter your card details), and your UPI ID will get created.