You killed someone, but you didn't make it clear in your dream, so it may just be an introduction.
The death penalty represents the beginning of a new life.
I suspect there are three possibilities.
1, you are getting married and leaving your family life.
2. Integrate into the social environment.
3. Leave your family to study
This is a new beginning. Cutting your neck means losing your original self.
Wearing a police uniform now shows that you are willing to trust them and make you change.
Looking for relatives-deceased, representing interpersonal communication and maintaining stability.
Many graves represent a restricted environment.
This is where you are going.