Its simple, you dont wash yourself after you use the bathroom. you lack hygiene, you need to keep yourself clean and i mean this in a VERY nice way.
If you dont clean up after urself, what do u expect to smell like? Its, obviously going to smell like ****?
Another reason could be dehydration, if you dont drink water your lower region is known to produce a bad odour , its either this or that u dont wash.
Secondly, with the pubes. When you shave down there, RINSE WITH WATER. SHOWER. USE A CLEAN RAG TO GET RID OF THE HAIR.
Literally, try focusing on your hygiene. I dont mean this in a rude way, but seriously.
how old are you?