king charles cav spaniel

Question
how do I get my 1 yr old male to stop marking his territory in the house? he goes to the door and goes outside just fine.

Answer
Try a belly band-you can find them on the internet.  It is a cloth "belt" usually with velcro, that covers their penis and either prompts them to not urinate at all while wearing it, or you can put a sanitary pad in it and will catch any urine that they release.