It is threaded correctly but you do need to catch the check spring in the tension as you go past. Some have a bar, some have a little path on the tension top.
The machine is a simple zz or ss.
It takes class 15 bobbins
The R button is reverse. Upper knob is stitch width.
The knob between the two and slightly to the right is your stitch length.
I know nothing about the many companies that made those machines.
A generic manual should be of some help.