PURCHASE FROM UNREGISTERED

You should put the figure in 3.1 Table in column D

sir if I put the figure in 3.1 Table in column D then it will ask me for RCM and I have to paid RCM as applicable but according to section 9(5) there is no need to pay of the same

If, you had purchased or taken services from GTA or an security services then you have to show the liability in table 3.1(D) of GSTR-3B and have to take Input Tax Credit in table 4(A(3)).
But, if you have purchased from another Unregistered dealers or other than specified above then these are exempted till Sep, 2019 so you have to put these values in table 5 of GSTR-3B.