Advice needed for filing tax

I just started my first full time job and will be filing ITR for 1st time next year, no one in my family has been in high tax slab previously so not much experience from there :D

Some questions:

• Almost 50% of my base pay is getting used in paying EMIs (Mostly mortgage) of my family, nothing is on my name, all on father's name, is there a way to claim this in deduction ?

• We have our own house in a tier 3 city and I'm getting 30k/month as HRA, what will be safe HRA amount to claim ?

• Can we claim any other expenses in deduction ? Leave travel allowance seems useless to me as I'm working remotely.

• Which tax regime do you prefer ? New or old ?

I could have done investments to save taxes but nothing is left after all the expenses and nothing on my name 😛