Many sewing machines can wind bobbins as the machine sews. This is done all the time in industry as it saves considerable time. The bobbin usually winds faster than expected.
Here is how it is done.
The spools are placed on the machine as shown in the first picture below. The black thread will be used to sew. The brown thread will be wound on the bobbin.
The machine is threaded with the black thread on the spool on the left.The bobbin will be wound with the brown thread on the right.