Question about keyword clustering

I've got a home assignment for an SEO internship job. I have a list of restaurants that do deliveries. Some include a name of a city, some include a name of a dish, and some are names of restaurants that I'm not familiar with.

I need to cluster these keywords as I like. With the keywords that include some sort of information I've found it pretty easy (clustering by city or dish), but I don't know how I'm supposed to cluster names of restaurants that I don't know. The list includes ~700 keywords.

How can I cluster all the "random" keywords?