Knitting mittens: stuck after the first finger

I’ve started knitting a pair of mittens and I’m confident I’ve done it all correctly so far. I’ve just cast of the first finger but now I don’t know what it wants me to do!
The pattern says:
With rs facing, rejoin yarn and pick up and knit 2 sts from cast on sts at base of first finger, k6, turn

That is word for word what the pattern is telling me to do and I just don’t know where to rejoin the yarn and the bit after that about casting on sts, can anyone help?

You pick up with a new skien of yarn I’m pretty sure it what it is saying… maybe someone can confirm this?

Rejoin yarn, pick up sts where you casted on thumb/finger then knit 6

Welcome to KH!
You cast on sts when you knit the first finger. So yes, as Annie Lauren mentioned, use a new end of yarn to pick up 2 sts from the sts that were cast on when you worked that first finger. Then continue with knit 6.
Here’s a video for picking up sts:

Which pattern are you making? Can you give us a pattern name or a link please?