Based on your questions I think your best option is to hire an experienced licensed Electrician for this project.
How to Wire a 50 Amp GFCI Breaker for a Spa or Hot Tub
Wiring a 50-amp, 240-volt, two-pole GFCI breaker for a spa, whirlpool or hot tub requires an understanding of the National Electrical Code (NEC) and the local electrical codes covering the wiring of spas. You need to inquire about any local regulations that supersede the minimum requirements set by the NEC when you apply for your wiring permit. Your city's Authority Having Jurisdiction (AHJ), usually your Building Permits Department, will supply you with a copy of the local electric codes upon request. Don't start this or any other wiring project until you have a wiring permit and have posted it on the premises as required by law.