Hi, welcome to the forum
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Do not panic, this fake antivirus can be removed.
Please follow this excellent guide from BleepingComputer. Step by step information, with pictures, is provided on the page.
http://www.bleepingcomputer.com/viru...antivirus-soft
Follow the steps exactly as advised in the guide. If you have a printer, you can take a printout, so that it will be easy for you, to follow the steps.
Now you know how to boot into Safe Mode. When selecting Safe Mode, you should choose "Safe mode with networking". In that mode, you can connect to the internet. Forget about the YouTube video... you should follow the above guide. You might have to download some softwares, as given in the guide.
If you have problems downloading them, then go to a friend's house, or to a cafe, and get the required softwares from there, in a pen drive.
If you have any problems, you can post here again.
Good luck
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