Bond order is the number of chemical bonds between a pair of atoms and indicates the stability of a bond.
Bondorder=2Numberofbondingelectrons−numberofantibondingelectrons
The given two molecules have the same number of electrons(14) like nitrogen molecule.
Hence, CO⇒Cˉ≡O+:BO=3
NO+⇒N≡O+:BO=3
The sum of the bond order of CO and NO+
=3+3=6