It would be helpful if you posted a specific line of your directions with which you are having trouble.
But, no the slipped st is its own thing and the YO is its own thing. You should slip one st from the left needle to the right, then do a YO creating a new/second st. Then work the next st on the left needle as directed. YOs are increases, so unless they are paired with a decrease you should be ending with more sts not fewer at the end of the row.
2nd row: purl, slip one purlwise wyib, yo 3 times. knit 11. purl, slip one purl wise wyib, yo 3 times.
Based on what you have written, you should be starting this row with 23 sts and ending with 29 as you increase 6sts from the YOs.