[still possibly hacked]

i need help cleaning my system, please.

[still possibly hacked]

yes i am, but have not been able to fix the problem. my computer is completely out of my hands.  i have tried everything i could think of. and i cannot do any of this because i am not the administrator.  and its only because a software has been set up on here. please help!

[still possibly hacked]

I have bought a new computer and bought the Malwarebytes software premium with it.  I did not download the Malwarebytes right away, it was probably 3 days later that I did so.  I have been under attack of malware and a malicious attack of viruses.  But not only that they are setting their own software on my computer and making them the administrator of my computer.  and I am solely the "owner"  of the computer.  It was confirmed by the geek squad of best buy that they had taken over the mothership of the computer.  And this was the only reason that I was allowed to take the computer back and to get another one.  I bought this in hopes of keeping all the malicious stuff out, but I feel as if they are on this computer already.  Im wondering if there is a way to set the settings to where when I run a scan it is made to look normal and nothing on there.  But when I go to my settings I see that there has been added applications that I have no idea what they are.  If anyone has any suggestions at all, or any ideas on what I can do to get anything that is not as a default on the computer off here, I would greatly appreciate it.  Thank You