1 ball? 2 strands? So lost

My best friend is having her first baby in June. I know it’s fair while away, but I’m slow at knitting. anyways, I got this pattern and I says I need 1 ball of 16 oz of yarn, which I have, but to do it double strand. I have no idea waht this means or how to do it. Any assistance is VERY much appreciated.

You can pull the end of yarn out of a ball, if it’s wound properly, from both the center and the outside. You can probably find the end on the outside easily. Can you appreciate a sort of opening in the center of the ball? Dig into there and gently pull out the tuft. Fiddle with it until you find the other end of the yarn. Voila! You have two ends, hold them together and knit as if they were one. You are knitting double stranded.

More trouble is to make two balls out of it by unwinding half into a second ball.

You use two strands of yarn at once and Knit with them as if they were one strand.
If you only have one ball of yarn,
you could take one strand from the center of ball and one from the outside and use them together that way,
or you could wind some from that ball into a separate one, so you have two half balls.

You can use both the inside and outside ends, but I much prefer to use two balls of yarn myself.

Thanks for your help!