To get an SSN I believe you have to apply for an EAD. You would file I-765 to apply for an EAD, with category (a)(10) if you were granted withholding of removal but not asylum. You would attach a copy of the order granting your withholding of removal. The EAD application in this category is free. On the I-765 it asks you whether you already have an SSN, and if not, whether you want them to automatically apply for one for you; say Yes. When you get an EAD, you can also apply for a driver's license. As to whether you can get a driver's license before you get an EAD, that will depend on your state.