How to model this ball?

It should be in two parts inner core is of cork and outer is of rubber the inner cork dia is 1.5" and the overall ball size should not exceed 2"
4 Answers

The main issue is the equal distribution of "studs" around the surface of the sphere.
There are dozens of "golf ball" examples, but most of them are wrong. Dimples do not follow circular patterns around the sphere, that is a very lazy approximation.
Equal spacing around a sphere is based on geometric polyhedrons.
Step 1. Determine roughly how many "studs" you want.
Step 2. Design a polyhedron with about that number of vertices. Geometry will limit the values you can have, but you'll be close.
Step 3. Use the polyhedron as a guide for the creation of studs, or for the creation of patterns and sub patterns.
Step 4. Finish off the round spheres representing the cork and rubber pieces.
https://www.chiark.greenend.org.uk/~sgtatham/polyhedra/
https://www.youtube.com/watch?v=4VLbncdnAWM
Clearly it is not finished, but hopefully this attached image gives an idea of the process.