I used the name Byron in my book stating it meant strong one. is that copyright infringement?
Copyright is legal protection of creative works. Facts are not creative works, and as such, they are not subject to copyright. The etymology of the name Byron, the altitude of Kilimanjaro, or the ways in which a strawberry plant reproduces cannot be copyrighted.
Summarizing those facts in a coherent text produces a creative work, and thus the resulting text is subject to copyright. There are also standards in academic writing about giving proper credit to the people who have researched those facts. But the facts themselves are free for anyone to state (unless they're secret or confidential), and the citations that are necessary in academic writing are not customary when making an offhand mention in a work of fiction.
You can’t copyright a fact or a name, but if you try to use an actual character from a copyrighted work, that gets more complicated. If you write a story about Harry Potter the British teenage wizard at Hogwarts, you’ll have a problem. If you write about Harry Potter the middle-aged accountant in India in 1831, you’ll be fine.
If you directly quote another source explaining what a name means without attribution, that’s plagiarism. If you paraphrase, there is no issue.
(I’m not getting into parody and other protected use, as I don’t think that’s what you’re asking about)
Names can not be copyrighted. You can use Lord Byron or any Byron in your story. You need to be conscientious about two things:
First names can be Trademarked — and often are for characters in Marvel publications or Disney characters. This isn’t a deal-breaker but complicates publication of the piece.
If you use a real person’s name and they take offense at your character AND they claim you are libeling them they can sue your publisher. Again, not a deal-breaker. There are many people named Clark Kent in the world and they don’t seem to be suing DC Comics. It just complicates publication of your piece.
Generally speaking, as the author you should never worry about stuff like this. It's a distraction from creating your best work. A publisher that likes your work will rationally assess the situation and work with you to mitigate the risk if they want to publish your work.