I cannot imagine how adding tasks would help speed up a schedule. Typically, removing work would be considered to help cure an unfavorable schedule variance.
Adding staff is a mix bag. It depends on the resource elasticity of the work you are performing, the environment in which the work is being done, the ramp-up time for the new staff, and about 100 other variables. Many here will cite the Mythical Man Month and tell you it is impossible. That's not necessarily true. Depends is the right answer.
You can make MSProject read anything. It won't give you answers except what you load in there. You need to re-estimate the planning values of the tasks remaining considering the extra staff and determine how risky the values are.
If you are able to evaluate your new estimates using Monte Carlo simulation, you may determine the likelihood your staffing intervention will return favorable results. There is a lot to simulating properly so you'll need to find an expert to help you with that. There's too much with it to answer properly here.