I have a homework assignment where I am given the flat pattern with all dimensions (bend lines, cuts, etc.) and I need to make the model and drawings from it. Is there a way to start from the flat pattern and then make the bends from that?
Yes, this is no problem.
Once you have the flat pattern modeled simply pick one 'flat' side or the other and select the "insert bends" command from the sheet metal command set. It will say that there are 'no bends found' but that's ok because we knew that ahead of time!
Once you've done that, all the rest of the sheet metal commands should be available because the part is now considered 'sheet metal'.
Now you should be able to work your way through the bends, (probably one at a time unless multiple bends happen to fall on the same bend line) using the 'sketched bend' feature, which is ridiculously simple, it's just a single line that represents where the bend occurs. Place and adjust these until you have completed forming the part.
No sweat! Good luck!