How do loose weight when there sugar in house?

im at the edge of average and over i have to go to a wedding in may and need to fit in dress, i kept saying i start diet in dec ye well sugar wont leave the hosue and my mom gets so maddd when i sya i need to eat healthy, what do i do? i like getting cheesesticks or pizza at school with cheetos, im always so hungry at lunch, what should i eat for whole day and exceirse exc, i cant go gym, have no pool