Computer Room Design

Im under 18, but im very interested in interior designing, includes the furniture etc. My family is going to move to a house, but my father would like to design each room specially. And told me that if i could, im the one who should design for it. Sometimes I draw on paper, but i heard that there is a software for designing a room or a house. Anybody knows the name of a simple software for it?Or are there any free software to be downloaded for free??bcos i have to finish it ASAP..

I’m taking an interior design class. our main project is a bedroom remodel. We have absolutly NO limits. I was planning on enlarging the room and adding a deck/porch. I plan on using colors like pale yellows and pretty greens. Does anyone have any links that could help me with flooring selections/paint colors/furniture/anything? Also, if anyone has ANY ideas then please offer them. It can be anything, so be creative!!
I am doing my own homework. Asking opinions of what looks nice to others is pretty important in interior designing if you ask me. I’m just looking for someone to say something that will spark some idea for me, as I cannot decide on a theme.

My family and I are thinking about moving and designing our own house. Well I need some advice for the best, most detailed Interior and Exterior designing software to buy for under $30?
Detailed as in where I can add different kinds of furniture, add a basement, a media room, and a game room.
Have any suggestions?

Thank You Very Much.
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