if you want to add a video, go to "videos" home page first. when you are in videos home page, you will see the "upload video" link on the left menu. click that link to upload your video.
yes you can manage to whom your videos will be visible. to do that, when you are viewing your video, click "video settings". when you are in video settings, you will see a section called "who can view this video". you can select who can view your video using the options in this section.
"selected users" is a useful option to keep your video’s privacy and to share it with the exact users that you want to. it works like that; you set a password for your video and other users who want to view that video need to enter that password. in a nutshell, no one can see your video without your permission.
when you are viewing your video, click "video settings". when you are in video settings you will see a section called "title". you can title your video here.
when you are viewing your video, click the "video settings". when you are in video settings you will see a section called "description". you can add or change your video's description here.