For beginner knitters, the most useful knitting abbreviations are co for cast on, k meaning knit, p for purl, and dec for decrease. Bernat knitting patterns use standard American knitting abbreviations, which assumes the knitter is knitting left to right.
Yo is an abbreviation for "yarn over," which means to bring the yarn over the needle knit-wise to create a new stitch. On the next row, the yarn over is knit or purled as part of the pattern and included in a stitch count for the row in which it was created. Yarning over is commonly used in lace patterns, as the stitch leaves a hole where it is worked.
Kfbl is an invisible increase stitch. The knitter purls the stitch and then knits in the same stitch, creating two stitches on the right needle from the one stitch. K2Tog means to decrease a stitch by knitting two stitches together at the same time, as if they were one stitch. This stitch creates a right-leaning decrease.
SSK is a decrease that is formed by slipping two stitches to the right-hand needle, knit-wise, and then knitting them together. This stitch creates a left-leaning decrease. Rnd means round. In a pattern, an asterisk after a set of directions means to repeat that direction for the appointed number of times.