Ransomware with mppq files type

My PC was infected by virus, all my data files type changed to mppq, and missing window 10 defender, if I purchase avg internet security and install to my PC now, avg can clean up my PC and also restore those affected files back to original? Please help me

Greetings,

We're afraid as the files that are already encrypted can't be decrypted.
You can try our protection to ensure that it stays protected against emerging threats in future. 
Meanwhile, if required, you can check the decryptors available at our end. 
Thank you for your understanding in advance!