In Oklahoma dagger, bowie  knife, dirk knife, switchblade  knife, spring type knife, sword cane, knife having a blade which  opens automatically by hand pressure applied to a button, spring, or other device in the handle  of the  knife, are illegal. 
this section shall not prohibit : 1. The proper use  of guns and  knives for hunting, fishing, educational or recreational purposes;The proper use of knives hunting/fishing/recreational purposes;
capable of inflicting injury in Parks/Malls/Plazas

1) First Question. How legal is it to slice, cut, or stab (to deter) someone unarmed trying to inflict bodily harm on me? What about if they are armed with a knife? Also I used the knife is only used as a last resort.

2) Second Question. When and where is it legal to use a knife for self defense?

3) Third Question. Where on the body are easy-to-hit spots to deter (not kill) your opponent in a self defense situation with a folding pocket knife? Also, How should these spots be attacked?

4) Fourth Question. What charges or penalties could I face for accidentally killing someone with a knife in one of the self defense situation above? I am a 16 year old, clean cut, white, male with no criminal record.