Need help with modeling an indeterminate beam in STAAD

Hi guys! I'm an engineering student and I'm still learning my way around staad. What I need to do is model the beam in the picture attached below, but I don't know how to do this. When I draw a 70 ft beam with nodes at points b and c, staad says it's disjointed. When i make separate members between those nodes, staad analyzes each member as a separate member and gives incorrect shear and bending moment diagrams. How do i do this so it would analyze the whole structure?

Thanks so much in advance!