The nether portal is unlocked by completing the "Aether Sprint" quest. In order to do so you must breed an athletic dragon and complete 6 evolutions.
Nothing. It is just decoration
In order to to the nether you need a portal.
A Nether portal is an obsidian structure that can transport players to or from the Nether dimension. USB doesn't come into it anywhere. The 'Minecraft USB nether portal' is just a YouTube fake.
walk in it
The get to the Nether in minecraft, you need at least 10 obsidian and a flint and steel. You need to make a Nether Portal, a 4x5 portal, and set it alight with the flint and steel.
Walk in the portal, and search for a nether brick building
If you are referring to the Nether portal panel block, which appears when a Nether portal frame is lit, its data value (ID) is 90. When placed without being in a Nether portal frame, you can still use it, however, you cannot place 2 of the portal block next to each other, or else they will both disappear.
Make a nether portal.
What the heck are the Netherlands? If you mean the Nether, then you get there through a Nether Portal. Plus you don't have to be in creative.
There is no way besides leaving the nether and making a new portal
No
A portal to the Nether requires ten Obsidian blocks (eco version) or fourteen Obsidian blocks for the full version.