Binding Off Question

When a pattern tells you to bind off 3 sts, is the first stitch you have to knit included in the number 3? So I knit one, then knit another and slip over, then knit another and slip over, then I’m finished?

Or does it mean knit one, then knit one and slip over 3 times? Because if you do that, it seems to take up 4 stitches to bind off the three.

You count the sts you slip over, not how many you knit. You are going to have to actually knit 4 in order to bind off 3, but then you’ll have a single stitch on the right needle that’s the 4th knit stitch.