Beginner question

What is the difference between a yarn over (yo) and yarn forward (yfwd)?

They can be the same thing - if you bring the yarn forward, then knit the next st in the pattern, it makes a YO. Sometimes it may only mean bring yarn forward to slip a stitch, but then the pattern usually says ‘yb’ to indicate move the yarn to the back between the needles. This isn’t a YO.