Hello, welcome to the website. My name isXXXXX can assist you with this.
You only have to repay the loan instalments that you have agreed to in the loan agreement.
You do not usually pay tax on a loan.
Also, you might be an admin fee for setting up the loan, but that should be included in the monthly instalments or be a one off payment up-front. Either way, you must have agreed to pay it for you to be legally responsible to pay it.