How to get privacy in my 2 bedroom apartment?

I’m a teenage girl in a 2 bedroom apartment, I hate to admit it but I’m severely envious of those with their own rooms, I only have peace when they go out, but that’s only once a week for a few hours or so when they go shopping, and my brother usually stays home with me,, and it’s like they all have their own “room” in their house and I’m like a nomad having to travel between rooms, and no matter how many times I’ve told them to not barge in ( at least 50+ times by now) they never even bother to listen or at least knock and it frustrating and I can’t really go to the gym or the pool since that’s technically a public place where people can see me, but al I ever want is just a nice small room all to myself with complete privacy where I can cry, study, workout, sing, and basically be myself to my hearts contact without people barging in, but if I ask my parents I’ll feel spoiled or demanding because I know that money is free and stuff, and I probably sound very privileged and I admit I am but I just want some non temporary privacy in my home for oncek.. (I’ll continue in reply’s because of the character limit for the post)
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Locking it won’t work because my dad, brother, or mom works in the same rooms as me due to the computer being there, and they come in to offer me food or they have to take a bath in the same room as me
How to get privacy in my 2 bedroom apartment?
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