Do a search on google or here....all this information is very commonly asked stuff.
Don't keep a male/female together. One or both will get killed.
Do some research on breeding bettas. There are several links about it here. It's not really worth it, IMO.
Bettas are already so common that most fish stores have no interest in buying your bettas from you. They're already cheap because they're so common, so the most you'd get is ~$3.
Also, once the fry mature (there can be 300 of them) you need to separate all of the males out and put them in their own containers. That can mean 200 liter containers that all need to be cleaned and water changed, fed, kept at the proper temperature, etc. It is in no way a small or easy task.