how do i make my main mesh fingers shorter

I'm not sure what mesh or model you are working with, but one way would be to use Proportional editing. This would allow you, in Edit Mode, to select the tips of the fingers, and then proportionally make them shorter. You'll likely have to experiment with the "falloff" type to see which setting works best. This is just a fairly generic answer for anything "finger" like that you would want to make shorter.