80 G donation limit

You may avail deduction u/s 80E provided such institute is an approved charitable institute (check with them if they are). Deduction can be claimed once repayment starts and can be claimed up to a max of 8 years.

No limit on the max deduction. Entire interest for the year can be claimed as deduction u/s 80E.

If no interest is paid, no deduction can be availed u/s 80E

80G deduction is related to contributions/donations made to charitable institutions (not regarding loan from such institutes)