Change Community Username

Hello. I setup my profile over a decade ago and I no longer want the username displayed for my posts to expose any personal information (surname). And, my current username is full of annoying, youthful arrogance.

I have read that mods can probably make this happen while I was reviewing other community posts seeking the same change, but I have yet to come across anything resembling concrete steps to be followed to make such a request of any community higher-ups and begin some sort of change process.

Can someone who knows what to do please point me in the right direction? Apologies if I've missed something obvious - it's been a long week and my most of my intelligence on vacation...

TIA