Random Number Generation Limits

Hi all, I am making an RPG with the basic level up kind of play. I have a counter that represents your attack (How much HP it takes out of the enemy) and I have that counter generate a random number every turn. Depending on your level, I would just have that number generate and then add extra to increase the number. Would there be a way to put limits on the random number generation condition, like instead of the range being 0 - 5 make it 2 - 6 or 5 - 8 instead of the last number being 0? It would make the whole thing a lot easier, I could just have it so that depending on your level the range increases. That would really help me out a lot! Thanks.