r/ampmodeling

Hello, I use a Scarlet 2I4 hooked up to my laptop running NAM or Amplitube and I wanted to model an amp to practice with. When I model it in NAM its so delayed its impossible to practice with. Am I meant to practice with it? or is it only to be used for recording? I also wondered if I was able to run my guitar to my scarlet to nam then to my amp but when I do that I only get my dry guitar sound