Can you use N's Resolve if you have no Dragon Pokemon on your Bench?
No. You have to have a Dragon Pokemon in play in order to play this card. The intention is that the main effect of the card is to attach basic Energy cards to your Benched Dragon type Pokemon, so if you don't have a Dragon type Pokemon on your Bench, you can't play the card. (You also can't play the card if you have 0 cards remaining in your deck.)
Source: TPCi Rules Team (2019-12-05)