Or have travel and other documents changed to reflect your reality. I did. I am a middle 'namer'. Ask anyone in my family for A. and they will asume you mean my cousin.
It took a bit of doing because it is a daisy chain. You have to get one document changed then the others will accept that in issuing a renewed document.
Now I have passport, driver's licence, health care card, credit cards, etc. all showing the same info.
A. BCDEF HIJKLMNOP
To use some sites - Expedia; etc. I had yo use A.BCDEF HIJKLMNOP
so all "personalized" communications now come addressed to A.BCDEF
In several years, I have only had one immigration officer (US) tell me that I should have my passport show my first given name.