How can I get my father's attention?

No one in my house listens to me :( My dad never has time for me but he has time to be in his room with his wife & if I dare go over she screams Juan I’m naked (even when she has clothes) or no not know come later or whatever :( & then when he finally comes out he leaves to work and so does she , I don’t understand this because they work together in the same hospital & they both have the hours of 3:00pm to 11:30pm & by the time they get home its 12:00am & throughout that whole time I’m taking care ofmy baby sister there 8month old daughter but please don’t say that its because they putting the attention on the baby because several years before the baby was born this was happening to be honest with you its been happening since my stepmom came in the picture even my other sister agrees she always wants him to be with her even if they been together all day , and me and my other sister can never be with him tell me how he said oh all 3 of us is going to have daddy daughter day were going to go to a restuarnt and the movies whatever you want but then my stepmom said stay home with me and our day was ruin .. but my sister stood in New York while I moved up here with my dad in PA- the point is that he won’t listen to me I’ll talk to him and as I’m talking to him he is walking to his room- and even if I don’t finish talking he walks right in and closes the door.. my stepmom no matter what she is always in her room and she don’t come out unless she going to work or is going out .. and my grandma she comes watches me when I baby sit because I get seizures and she just watching like in case I get a seizure she can take the baby … but she also ignores me , its probally because of the baby because she never done that to me before yet still I feel mad alone , and I can’t even go out because I’m always taking care of the baby and I get exausted so the two days that I don’t have to baby sit I just stay home and relax .. not even one of those days my dads off and I still got to take care of her & yes I have told my dad this before that he doesn’t listen to me or pays attention to me and all he says is well and shakes his head :( and then I told him again after the baby is born and he said what you want me to carry you like I carry abby?? your a teenager ? like what does the fact that I’m a teenager has to do with anything?? O.O :’( please what should I do to get my dads attention or anyones attention in my house :(