EDIT: TL/DR Have you tried white noise?

​

I won't go into to details, but I have a problem with filtering out sound at times. It's as if my lizard-brain just gives up and says, "Okay, here is all the sound around you. You figure out what is important."

Earplugs don't work for me. It just makes it feel like I have extra-pressure in head, like a head cold. And every sound inside my body is amplified. Walking, chewing, breathing . ugh.

When I need to concentrate, and there are too many noises in the environment, I found I can use white noise. I found a good white noise generator at Amazon for under $30US. It produces a dozen or so different tones, and they don't have immediately recognizable repeatable pattern. That turned out to be important to me, because finding a pattern in the "white noise" was also distracting.

There are lots of white noise generators around. Alexa has many, for example. There are web sites that generate them too. Some are free, some charge. You need to be careful around some web sites tho.

I mean, if it says its "free" but insists i t needs to install some "free software" just to play a sound for you, it is probably loading viruses, worms, or other malware instead. A web page is easily able to produce a sound without adding more to your computer.