A portal to the nether is relatively simple.
Supplies:
14 obsidian blocks
flint + steel

1. Make a frame 3 blocks high and 4 blocks wide out of obsidian.

2. light the bottom

Your'e all set!
If you have any problems this one is on you. I explained this as clearly as possible. If you want obsidian, I have a blog on an obsidian generator.
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