Alert of malware

MalwareBytes is the only Malware software recommended by Apple Support. But only when needed. In this case, you may very well want to download the free version and run it.

https://www.malwarebytes.com/

Use MalwareBytes, as Randall_2023 suggested.

While the link from AlWeir is essentially correct (it's malware you managed to install somehow), note the manual removal instructions are obnoxiously tedious. Which is deliberate. What these sites really want you to do, and is very typical for such sites, is they push you to download the removal tool.

Thomas Reed, a member here who now works at MalwareBytes has said these kinds of sites are all over the place and are usually downright dangerous. The cleaning tool they want you to so badly download and run are almost always worse than what they claim to be for.

https://malware-guide.com/blog/remove-ciscod-will-damage-your-computer-pup-from-mac