I wish to surrender the Under-construction Flat which the builder has been delaying for last 2 years

We had purchased a flat in Mundwa Pune April 2018, While it was promised to us that we would get the possession in next 3 months. The loan amount sanctioned by the bank is 22,00,000 ₹ for 15 years. 14,00,000 was disbursed initially and remaining balance was supposed to be done after completion of work. During this I was paying a pre EMI of 14 k and once fully disbursement of payment the amount was to be 26k per month. Since then there has been delay with the construction. It's Feb 2020 the property is still under construction, the balance disbursement is halted coz the work complition is not been done. And now the bank has converted the loan of 14 lakhs for 5years and won't be disbursing the remaining 8 lakhs. So now for an under construction property I am payin a whole emi of 26k every month since November 2020. The builder is not responding to my calls the project doesn't comes under RERA. Paying 26k every month and still not owing a house is big burden for me. In this situation I feel I should surrender the house. 1) But the house is under construction will the bank take the property which is under construction? 2) If I stop paying EMI will the bank take any legal action against me? 3) Can I take any legal action against the builder? 4) what's the way out here?