How to undo a yo a beginning of row?

I started a simple shawl which starts with a yo followed by k the rest of the row. My very last row I make a mistake and I can’t seem to correct it. I have gone back several rows even working one stitch at a time. So frustrated. i would love some help.

Welcome to KnittingHelp!
What pattern are you making? Can you tell us the pattern name and give us a link to it?
Ordinarily, you can just drop the yarn over since it doesn’t use a stitch but is simply draping the yarn over the right needle.

I am making a triangular shawl for beginners.
The pattern is to begin each row with a yo and knit until the end of row.

Where did you find the pattern? Tink back a row being careful to pick up the yo. You might need to knit into the back leg if you pick it up twisted. Once you’re confident you’re back on track you can add a lifeline to rip back to should the need arise.

Is it similar to this pattern?
If so, just start the next row from where you are now, beginning with the yarn over.