If you are at this stage carrying out a feasibility study, ascertain what the market will need provide for. Determine the types of aircraft that might need to use the runway. Then go on line and determine what runway length is necessary for near sea level operations with the temperatures that you would expect, and what take-off landing weights are expected.
Determine who the civil aviation regulatory authority to determine whether they comply with ICAO Annex 14 Standards and Recommended Practices, if not what are their differences. Then get yourself a copy of Annex 14 Part 1 from the ICAO website. Annex 14 will give you the basic runway dimensions and what adjacent areas have to be free of obstacles.
If you have any general questions PM me. I'm just an hour drive away.
Caution there are a lot of cowboys out there who will be happy to take your money for dubious advice.