Hi and welcome!
You're going to knit the bottom of the foot, the sole first and finish with 5 (or 7 sts) on the needle depending on the size you're making. Knit the 5sts and then pick up 43sts around the edge of the sole. So pick up sts along one side edge (the end of the rows just knit), across the cast on edge and then along the other side edge (the other end of the rows) and finally join to knit in the round with the final 5sts. It's as though you're picking up sts around the sole of a shor to knit the upper part.
Best to edit the pattern to leave out the final instructions after the red so we don't get into copyright problems. We can understand the pattern with just the beginning instructions.