Questions about area and royalties in general

It has been brought to light that my great-grandmother has had interest in mineral rights in Grady County in Oklahoma. Me and my family are in the process of probate to get the mineral rights into our name. My great-grandmother owns a 1/8 steak in s/2 sw/4 of section 19, township 9n, range 5w that I understand to be underneath Rowan resources at this time. I was wondering how the lease and royalties are done, as well as any information on this area. The wells that I’ve been told that she has the same interest in are the Wilkerson Wells and also American pharoah. If anybody can help me understand how the mineral rights and Leasing and royalties are done also just a general understanding how everything works. It would be greatly appreciate it.