dear
As per below section reproduced here, in my view Loan should be taken by assessee and should be paid out of his income chargable to tax. In case it is paid by joint bank account then proportionate amount which is your part of income, shall only be allowed.
Moreover remaining part shall not be allowed to your father as he has not taken loan in his name or for his relative. It is you only, who is taken loan.
[Deduction in respect of interest on loan taken for higher education.
80E. (1) In computing the total income of an assessee, being an individual, there shall be deducted, in accordance with and subject to the provisions of this section, any amount paid by him in the previous year, out of his income chargeable to tax, by way of interest on loan taken by him from any financial institution or any approved charitable institution for the purpose of pursuing his higher education or for the purpose of higher education of his relative.