Advance Tax on LTCG on sale of property

I am a senior citizen having sold my ancestral property on 01.07.2025. 1% TDS on total consideration is already deducted by the buyer. Presently, I intend to pay tax on total LTCG. My query is

 1. Whether advance tax is payable? If so, at what rates since 15th June is over?

2. What if I decide to take benefit u/s 54 or 54EC later on?

3. Whether as senior citizen, is this advance tax exempted from prepayment? 

Thanks in anticipation.