17 stitches per needles works out if you're using 5 needles, 17 stitches on each of 4 needles and knit with a 5th. As for ribbing, when working in the round, you knit the knit stitches and purl the purl stitches. When knitting stockinette in the round, you knit every round unlike flat knitting which is knit a row, purl a row.
Your pattern is incomplete. Do you have the rest of it where you make the heel flap, turn the heel, pick up stitches for the gusset, decrease the gusset stitches, and knit to the toe, decrease, and finish with the kitchener stitch?
Here's an easy pattern. If you print it, you can highlight the instructions for the size you're knitting:
How to do kitchener stitch also known as grafting: