If you want the video posted in Videos module to appear on the Home Page (Main Activity feed) automatically, then you need to enable the Display Setting for "Main Feed" from the admin panel.
Please go to "Admin" > "Settings" > "Activity Feed Settings" > Click link "Activity Feed Item Type Settings page." then choose "Video" in plugin field. After that check the "Main Feed" option in the Display field and Save Changes.
If there is any other concern you have then please share it.
It seems that you do not have the Video module which is why it is not shown in the "Plugin" list. Can you please let me know where are you trying to insert the video?
Are you trying to post a link for the video or trying to embed in a widget?
If you can provide these details, I will be able to help you out in a better manner.
Video module comes with the Musical or Advanced package. You can upgrade your package to Advanced (Most Popular) from here: https://www.socialengine.com/products/php/pricing.