You have to push that tab with the "bullseye" to the left and leave that slide plate open while the bobbin winds.
The machine should be threaded as if for sewing and set up for straight stitching - make sure you're not on the Buttonhole setting.
Raise the presser foot, pull a couple of inches of thread through the needle and wrap it around the screw that holds the presser foot on and hold on to the end of that thread, turn the speed to "Slow" and push the foot pedal or knee lever to start the bobbin winder.
Run it steadily, not fast, until the bobbin fills to the fill line. (on the bobbin, it's the second line in from the outside, I think)
Then you close the slide plate, which pushes the bobbin winding tab backing into normal sewing position, pull a couple of inches of slack thread though the needle plate and start sewing.
If that doesn't work, let me know and I will dig out my T&S.
The gears on these later T&S machines are self-destructing nylon and pretty much disintegrate at some point. If you haven't had the gears replaced on it, it might be failing gears that's causing you so much trouble.