The issue i'm having is trying to model the triangular hole with 3 arms on the left(2nd pic). I can not, for the life of me, figure out how to make this into one piece (i have all 3 arms made but i can't figure out how to connect them). Needless to say i am extremely frustrated. Any help would be appreciated.
In class, my instructor showed us how to manually make a mesh, or individual patches, using two circles, one above the other, and connecting them with a vertical curve. He was able to snap the end of the curve to the circle and therefore define 'patches' that went around the circles forming somewhat of a cylinder. I clicked every possible option trying to connect the end of a curve to every possible shape i could make and got nowhere.

please help