The short answer is yes. If you can calculate results manually using the input parameters, then Creo is capable of using the same inputs to make calculations and update the model geometry using the inputs and calculated results. There is more than one approach to capture this design intent and then use it to update the models that can work.
You can start by defining relations in Creo that produce the calculated results from the user inputs, this is pretty straightforward. You can then use these results to drive/update the model geometry of the components in the gear system. Building the mode to exploit the parameters is what most users will have more difficulty with.
I would consider using a Notebook as a strong contender to capture the design intent using the input parameters and making the calculations needed to update the gear geometries. You can capture the inputs and derived results via relations in this file and use it to drive any model as required.
About Notebooks
Refer to this related thread to see an example of a notebook used to drive the geometry of a crank/slider mechanism for an engine.
Solved: External parameters in assembly - PTC Community
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Involute Development, LLC
Consulting Engineers
Specialists in Creo Parametric
