Help with a pattern

hello…i was wondering if anyone would be able to help me with a pattern i’m working on? this is the link to it: (just in case the above one doesn’t work, hopefully someone won’t mind copying and pasting)

basically, my issue is after row 24 to the end. I’m not sure what the pattern means when it says to thread the yarn and bind off.

the other problem i have is when they say to cast off on row 25…i have no clue what that means…

so if anyone is able to help me out, or provide me with a link to even a video on the site that could help, i would really appreciate it…thanks in advance!

Cast off is another term for Bind off.
After row 24 it reads -
“Thread yarn through remaining stitches and bind off, taking care not to distort the shape.”

You don’t really bind off when you thread the yarn through the sts, you just weave them through the sts on the needle like a drawstring, but not too tight so you keep the curved shape at the top.