If you are fortunate to have ancestors that kept a coat of arms then you may be able to get a lot of the 'story' as to why they did things the way they did. To research the meanings of various symbols used on shields, etc go to:
Coat of Arms - Meanings:
https://www.irishsurnames.com/heraldiccharges.htm
Although there are a wide variety of companies that claim to produce Family Crests and Coat of Arms by mail order, one must pay close inspection to ensure that the background research into the name is relevant to your pedigree and not merely a means to sell false information.
I have a copy of my families coat of Arms. I have researched it and it has proven to be correct. It is of a noble family family. That is going back on my fathers dads side. My fathers mothers side is the one that gives me my royal blood. I have not got my coat of arms for that side of the family yet. On my mothers side I have some of three ceremonial swords that the nobility wore to balls and other functions. It has the coat of arms and the surname on the sword.
There are some generic ones of my family name circulating the net but I don't know how authentic they are I think some of it might be wishful thinking or in this case an artist's rendition of what he thought might look nice for the family coat of arms.