My question is I have a mini rose bush, in doors. how do I care for it? It doesnt look good

Mini roses bushes are really best grown outdoors like the big ones, they need plenty of humidity, semi moist soil and indirect light to do well.
Like indoor ivies, they can easily get infested with spidermites if the conditions are right, so I would check the leaves for them and fine webbing.
If your mini rose makes it through to the warmer months, you can plant it outside in a semi moist area that gets some sun and some shade, and if your lucky like I was, it will come back after a cold winter in the spring.