Android help - Your samsung is infected with adware viruses, how do I get that to stop??

Reset Device to Factory Default settings,

Before going to Reset Device ,

Open the link and select" 2 step verification On " > Sign in ,

Scroll down to Backup codes,

Set-up Backup codes and/ or  copy the current codes,

These codes are high-priority so you should keep them out of Account and Device,

When you set-up Device and Sign in to your Google account,

You should be able to Sign back in to your Google account with these code while other options may be delayed  because Device is on set-up,

If you have Google Authenticator app,

After Reset Authenticator will be reverted to its initial stage without any codes and Accounts,

Make sure you have substitute options for Sign up in Third party Apps or  websites,

Or, Export Accounts From Android to Android,

Next,

Check Sync settings,

Next,

Backup Data,

Next,

Save  / Backup your Passwords /  Data / Files / Photos / Videos  / Contacts / X/ X/ into Google Account,

Save Third party Apps Data which are not allowed to Sync with Google Drive / Account ,

Next,

Open the link,

Switch between accounts and,

Confirm Default Account for this Device,

Next,

Remove All  Accounts,

First of all remove Non default Accounts,

Finally remove Default Account,

Next,

Reset Device to Factory default Settings,

While Set-up Device  Select Set-up as New / Copy your Data,

In your case Set-up as New Device ,

If you select Copy Data ,

Your Call history , SMS history, Personal dictionary ( for the previous same language), Device Settings such as Screen display Settings and Sleep Time  Settings will be Restored From the just prior Backup,

System and Non System Apps will be Reinstalled,

If you select as New Device ,

Device Reset to Factory Default stage,

System Apps will be Restored,

Google Non System Apps Data will be Restored,

Third party Apps Data which are allowed to Sync with Google Drive will be Restored, for example WhatsApp and Password Manager Data( only after the Apps are Installed ),

Non System Apps will not be Reinstalled automatically,

After set-up you can find your previous Apps here,

Due to the Reset  Upgraded Android version will not be degraded,

After finishing,

Select Automatically Sync Data On and Check successful syncing in Apps,

Next, 

Backup Data,

Next,

Open Google Play store and Install " WANTED"  Apps only,

BE AWARE  of install Apps out of Google Play Store,