“This is an incitement trial.”
Page 3 of the charging document states that Trump repeatedly made false statement about the Presidential election fraud.
In the country, you get to answer to the charges brought. We’ll see what the leaders of the jackass party do as they are made to suck on their own charges: https://www.cnn.com/2021/01/11/politics/house-articles-of-impeachment/index.html
Supposedly, but only in a judicial proceeding. Impeachment is a political proceeding and rules of evidence, etc., don't apply. The Senate makes the rules for how it is conducted. Impeachments are meant to be "show trials".