It means that the web address isn't valid, or correct.
YouTube can definitely be a valid source depending on the channel and what you're looking for. For instance, many companies and organizations do use YouTube to make announcements and various other videos. In fact, the U.S. Governement also has a YouTube account, which would probably mean that YouTube has at least a couple of credible sources.
www.Youtube.com
Yes. Any valid state issue I.D. is valid for enter and exti Puerto Rico.
You can subscribe to them by going to their website, going to the bottom of the page and clicking on the subscribe link choose a team and enter you valid email address.
You only need a valid passport to enter Mexico.
A valid passport, and a valid visa.
Log in to YouTube and go to the YouTube Studio (click your profile image and select YouTube Studio). Click Monetization in the left navigation menu. The monetization page will track your progress toward reaching 1,000 subscribers and 4,000 hours of Watch Time.
Maybe you already have a YouTube account. If you are sure don't have one, then create an alternate email for use.
Any email address you enter into a web-site must be legitimate. The web-site is able to instantly check whether or not the email you enter is actually a valid (real) one !
Not anymore.
There is no code for this game.
Yes, it is possible.