Need Help: Dog Is Clingy and Anxious

My dog is super clingy and anxious. She barks when she hears car doors close, barks when anyone is eating because she wants fed, barks while cooking, cleaning etc. She wants to stay right up against us when we are laying on the couch. She barks when she wants rewarded for things she does in the middle of the night while we are sleeping. She struggles to play by herself as well. She knows basic sit, stay, down commands but she is very dependent on our attention. We don't know what to do to help her relax and be more independent. We would like her to be able to ignore car doors shutting, knocks at the door, food temptations etc. and would like her to not be as clingy. Does anyone have any recommendations as far as training programs that may help her? Thanks in advance!