At least not the simple types that most people wear. They're mainly intended to reduce the amount of virus expelled by the wearer, reducing chances of infecting others. How well they do this is still a matter of scientific debate.

I don't know the numbers for the US, but my country (Netherlands) and the rest of the EU are knee deep in the second wave and most spread seems to be associated with private occasions (birthdays, bbqs, funerals, etc.) and work.
So yes, people who can't work from home are at a higher risk. Especially because they tend to work in industries with suboptimal conditions. The meat processing industry saw a lot of outbreaks, for example.

Bars and restaurants seemed to have a relatively modest part in the spread during the time where they were allowed to open (shut down right now), probably thanks to most of them adhering to rules and guidelines (limited admission, no dancing or singing, distancing).

Teachers are seeing a relatively high number of positive tests, so while children and teens are at low risk of getting ill, they're probably an important vector for spreading the virus.

Does the CDC still publish numbers? Is there something like a dashboard or flowchart for the public? Like https://coronadashboard.government.nl/ for example? My government handled it far from ideal, but at least they're still engaged, can't imagine how anxiety-inducing the total lack of oversight must be for people in the US.

(chances are some of the info I have is already outdated, so I hope people feel free to fact-check me)