Chill-tab
How to remove Chill-tab from my mac
Run the diagnostic tool Etrecheck and post its report here.
It may also offer a button to remove this chill-tab thing.
If Etrecheck does not let you delete this, download and run the free version of MalwareBytes.
Do not fall for any of the "cleaners" out there that claim to clean stuff, optimize, and speed up your mac.