Q.potted angel Trumpet pruning
I have my first Angel Trumpet, which bloomed beautifully this summer. It is in a large pot so I carried it inside for the NJ winter months. It lost most of its leaves but has now started growing again. It is in a window with some afternoon filtered sun. The plant is about 5ft. tall with a Y branch almost at the top. I would love to prune this but am afraid of killing the plant. There are 2 long 2ft. branches from the Y. Please help. How and when can I prune this and can I root the pieces that are cut off?

You should hold off pruning now, as it is not in a dormant period.
Here is some links with more information.
https://www.gardeningknowhow.com/ornamental/trees/brugmansia/brugmansia-winter-care-wintering-brugmansia-in-your-home.htm
https://www.gardeningknowhow.com/ornamental/trees/brugmansia/growing-brugmansias-in-containers.htm