It looks to me like you made a yarn over there…which is easy to do on a knit, purl repeat. Keeping the yarn in front and knitting the next stitch = yarn over. This will look like a little hole if you work a stitch with the yarn over on the following row. Unfortunately I don’t know of a perfect fix without ripping back to it. Picking up a dropped stitch is much easier to do!
@leafydecays I started out learning on YouTube! Now 12 years later I teach crochet on YouTube 🙃 My best advice is to start small, embrace mistakes, and never give up. Every project will look better and better!