Welcome to GoDaddy Community! Thanks for posting your question.
The malware warning that Google places on a site usually has an option to get more information, especially if you try to visit the site in Chrome. Usually it will give you detailed information on what to do next. You can also review the instructions here:
You may also want to reach out to Squarespace if you have any issues cleaning up the site. Perhaps others in the community will also have pointers for you.