Your computer is infected with
ransomware. You will be able to get rid of it, but you won't be able to de-encrypt all those files - and I do not recommend that you following the instructions in the text and pay any money.
Those files are gone for good, I'm afraid. To protect any future files, invest in a good antivirus program and use Malwarebytes too:
Malwarebytes 2024 protects you against malware, ransomware, and other advanced online threats that have made antivirus obsolete and ineffective.
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