Those are boxelder bugs, not beetles but one of the many insects commonly referred to as 'true bugs '. Though they can often be seen in large swarms like this, reports of significant plant damage are rare. These insects specialize in feeding on the seeds of boxelders and other maples.

If your home is not well sealed, boxelder bugs will find their way inside. Do you have a portable vacuum?

Box Elder bug. Some people do vacuum them up which distrurbs them enough that the release that distinctive odor. My wife will trap them, gently, and flush them. As stated clearly in the link below do not use any insecticide in the house to control these wee buggers.
In my case any thing that might control these would trigger an Asthma attack and make the house unhabitable for me for over a week.

Here is a link that might be useful: Box Elder Bugs

get rid of the box elder tree ...

you will never get rid of them..

and there is no real reason to do so ...

and if they are in the house.. its a 'house sealing' issue.. not a bug issue ...

the few that get in.. i just grab with a kleenex .. and feed them to Poseidon.. via the inter galactic whirlpool of death ...

they will be gone with the first hard frost or freeze .... until next year, of course ...

ken

ps: i flush them...

"the inter galactic whirlpool of death .."

Ken, you are always funny, but this may be your best yet.