Many stories in the Bible are figuratively. The story of Adam I use figuratively, to learn some important lessons. I don't use the word sin
The lesson I learn is that humans have to listen to God [their conscience]. Following their desires and not their heart will lead to trouble
For many centuries they claimed Adam to be the first man on earth; around ca. 6000 years ago. My Master said that Rama lived 20.000 years ago [and he was for sure not the first]. Science says that humans existed maybe more than 200.000 years ago. So this whole story of Adam and original sin is based on Adam living ca. 6000 years ago. This fact is false IMO. So this whole "sin" story is false IMO. So also from this POV I prefer to use it figuratively.
This sin story was invented in the year 200+ [says wiki], so it's not literally said in the Bible, but it's just an interpretation of Bible verses:
[wiki: The concept of original sin was first alluded to in the 2nd century by
Irenaeus,
Bishop of Lyon in his controversy with certain
dualist Gnostics.
[4] Other church fathers such as
Augustine also developed the doctrine,].
Original sin - Wikipedia
Your question "So you believe Adam's actions and sins are of his own?" is a tricky question:
* If Adam was
not the first human then
original sin makes no sense.
* Seen from pure Advaita "only God exists" then there is no Adam different from God, so this question does not apply
* As far as I can see, this whole "Adam + original sin" is just speculation
And as I already said "the concept of original sin" will make people less responsible for their actions, so not a smart concept IMO. So then it's also understandably that they do not accept "collective responsibility" for the examples you gave either. So seen from this it's also not a good concept IMO