Reg huf, can i add only one unmarried son as coparcener from my 2 son

and date of creation of HUF?

Karta of HUF:   SUrinder Garg    DOB: 28-01-1956

Wife of Karta:   Kiran Garg        DOB: 12-12-1960

Son of Karta:    Naveen Garg      DOB: 10-01-1993

in above case whats the date of creation ? , Surinder Garg is able to get cheque from his Father if it requires

Surinder Garg has a another Son Puneet Garg but he dont want to add in HUF because he is a Govt Employee