Home Improvement Contractor - Licensed Contractors - Best way to get contractor Liscence to work on houses eg. roofing, plumbing, carpentry, landscaping?

Best way to get contractor Liscence to work on houses eg. roofing, plumbing, carpentry, landscaping?

I want to know whats the best way to go about getting a liscence for working on houses. I have some cash flow and is looking to buy a fixer upper...