All I want to do is simply display a static character inside a viewportframe. I tried it, but the character didn't show up. What do you have to do?
Viewport frames are easier than you realize. They are basically 3 dimensional workspaces plastered onto a gui, so to get things displayed in them, you just have to parent the object into the viewport frame.
So in your case, you would put the character or it's clone parented to the viewport frame. But the thing you might've had difficulty with is that you didn't set the viewport frame's camera. They have a camera independent from the workspace.CurrentCamera, so you have to instance a new camera, parent it to the viewport frame and use its CFrame to aim it at your static character.