This is an educational thread. I've spent the last 10 or so years on a research project about ancient Rome...

Again, no, he was adopted.

do you consider gladiators to be more like wrestling in that they wore elaborate costumes and put on a show for the people, or was it a real contest between combatants...

inb4 I know close to nothing about Rome, but am curious, so don't shorten the explanation.
How hard was the work for most of the people? And how were the life standards in general?

Roman military tactics evolved over a long history. Hence uniforms and armor changed significantly from the period of the Republic (say, 200 BCE) to the end of the Empire (say, 400 CE). What you're asking is essentially like saying "why did American soldiers wear one sort of uniform in 1776, and a different uniform in 2020?" So if we're talking primary changes, it's just time and styles.
For some reason that's always puzzled me, popular media likes to show soldiers from the end of the Republic and the beginning of the Empire. Maybe that's because that time period has the most interesting stories. Or maybe because Hollywood knows that we will recognize that as 'Roman'.

In your opinion, what major takeaway can modern Western society learn from the collapse of the Roman empire?

gay is bad

It was real. Not everywhere and not at all times- graffiti from Pompeii tells us that gladiators had more agency than we normally think. And people have a natural tendency to not kill others. But combat was their life and livelihood. And their culture was a vicious one

Ty. Say Im the child of blacksmiths of some shit, Im a citizen but not noble or particularly rich or anything. I want to educate myself. What are my options and limits to what I can achieve

Dumb question but, how much Ancient Greece influenced Ancient Rome ?

Romans usually didn't work. Work was done by slaves. Was good to be Roman.