Adding Modifiers to Concentration Roll

First time DM here, I am designing a spellcaster for my campaign using the NPC sheet and was wondering if there was a way to add their INT modifier specifically just to concentration checks. I read about macros but I am not 100% sure if this would be the solution or if there is an easier one.

Any help would be greatly appreciated.

What game are you playing and which character sheet are you using? If you’re not sure please supply a screenshot. 

I'm playing 5e and using the character sheet 2014 to make the character, though I'm using the NPC sheet if this makes a difference

Just tried this and it worked perfectly, thank you so much