Hi, since 2019-20 I didn't fill my ITR. How can I do it now? Please guide.

Can you please suggest on capital gains as per Indian taxation laws arising in the below two queries : 1) property purchased with joint ownership, me and my wife’s name in 2015 at a cost of 64,80,000, housing improvements done for the cost of 1000000 and brokerages of 200000 paid and sold the same property at 10000000 in Dec 2023? 2) 87% of the proceeds got from the deal i.e 8700000, have been reinvested to pay 25% amount in purchasing another joint ownership property in Dec 2023, 3) I have invested in another under construction property in Nov 2023 by taking housing loan, which is on me and my wife’s name worth 1.4 cr, here the primary applicant is me only while wife is just made a Co applicant in the builder buyer agreement and also on the housing loan . So what are the LTCG tax liabilities arising from the above 3 scenarios for FY 2023-2024 and FY 2024-2025. I intend to sale off the property acquired in (2) by Dec 2024 and use that proceeds to close the housing loan for the property acquired in (3), will this sale of property be inviting any tax liabilities if the complete proceeds received from the sale of the property in (2) would be utilised to close the housing loan taken in Nov 2023 for the property in (3) ? Since in FY 23-24, I would be claiming the LTCG from the sale proceeds of 1) invested in the purchase of property in 2), and I intend to sale off this property in Dec 2024, will the LTCG claim be forfeited on the property sale in (1), should I hold this property at least for further 1 year so that sale of this property in 2) will not invite STCG?