Modify node, arras theme

Hello

I wanna change the node of the post in the Arras Theme. The node lets see the day, the month and the year of the post, but I want show also the hour. In the other side, I dont want lets see how many comments have the post; I want to show the first category of the post (The first because is possible the post have more than just one)

Here a pic of the standar node: https://elmapurite.com/images/normalnode.png
Here a pic of the node that I want: https://elmapurite.com/images/node_iwant.png

Thanks in advance

Greetings!