TCD and most other universities in Europe are easily as good as any American 'schools', and many are better.
There is none of this nonsense with fraternities or sororities, but there are college clubs you can join, so there is the option of a social life - but if you're going to study medicine, you won't really have much opportunity for that.
If you want to find out the details of the course, my advice would be to go to the college website and read what it says there under the Faculty of Medicine.
Dublin is great fun, but expensive.
The people in Dublin are like people anywhere else, but rather more likely to talk to total strangers than your average American.
As an American and non-EU national, you will be paying full fees, but it will still be nothing like the extortionate amounts American universities seem entitled to demand. However, the cost of living in Dublin is not cheap.
To apply for university in Ireland, you go to www.cao.ie. Good luck.