Transfer of business to his son

Yes it's possible

Yes you need to file FORM GST ITC 02, also certification from CA required where amount of credit to be transferred exceed Rs. 2,00,000

File GST ITC 02 from the common portal of transferror and transferee need to accept the same under his GSTIN (Quoted by transferor) upon which all the credit lying in electronic credit ledger of transferor shall stand transferred to transferee.

First you will have to create a transfer agreement.
Then if you have any itc balance you will file itc-02.

@ shreyansh ,but in my case there are no change in constitution of firm

Then also it is possible