Types of Bonds can be predicted by calculating the difference in electronegativity.
If, Electronegativity difference is,
Less than 0.4 then it is Non Polar Covalent Bond
Between 0.4 and 1.7 then it is Polar Covalent Bond
Greater than 1.7 then it is Ionic
For N and Se,
E.N of Nitrogen = 3.04
E.N of Selenium = 2.55
________
E.N Difference 0.49 (Weakly Polar Covalent)
As you have not provided remaining pairs, so if you have any of them, follow the method as mentioned above.
