Often dreams are an unconscious attempt to solve a problem. In your case, the problem to solve is your relationship with your parents. Since you haven’t resolved it in your waking hours, you keep working at it in your dreams. A more useful approach would be to deal with the problem directly. Clearly, violence isn’t the answer. Conversation might be.
By all means, if you can, talk to your parents as the mature adult you are. That means being calm and rational while reviewing the past and working to establish a different kind of relationship for the future. Give them credit for whatever support and security they provided for you while you were growing up. Allow for conversation about what you all wish had been different. Share your hurts and accept whatever reasons and apologies they are able to give.
If a rational conversation isn’t possible, remind yourself that the past is in the past and that your focus needs to be on the present and future. You might find it helpful to take some emotional distance from your folks while remaining respectful. You didn’t mention whether you continue to live with them. If so, start making concrete and specific plans for moving out.
Not everyone gets the parents they wish they had. You are not likely to be able to change your parents. They are who they are. The good news is that you are 20. You are no longer a helpless little kid. You are no longer dependent on them.
I wish you well.