You upload them to Youtube and save them as an UNLISTED link.
The post the link.

First of all - the signup page has a video on it called "How to take the online lessons"
and if you watch that - it contains direct instructions on where to post them at 1:04.

Second of all - learning the guitar and getting good at it always contains DECADES of frustration - of which
one works through. You signed up for lessons on Jan 31 and promptly QUIT on Feb 4. Your questions show
a great deal of impatient frustration - like you are expecting someone to hold your hand and give a silver platter.
This kind of attitude will get you nowhere on the guitar and ANY other instrument. You quit lessons even before
you got started.

Third - since you quit only 4 days after you signed up, this makes you NO LONGER a paying student, so you dont have to bother uploading videos anywhere.