help with a couple things?

[MINNESOTA FATS]

first off, is it advised to have a straight back when down on the shot as i have quite a curved/hunched spine when playing my shots wondered if straightening it out would help in any way,also im left handed and when cueing through i feel like i cue slightly up towards the left top of the cue ball i can tell this as when i play a lot of top spin when it hits the cushion it usually comes off to the left instead off in a straight line as if i am moving the cue slightly towards my body on the way through, wonder if anyone may know the reason why this is happening

[CoachGavin]

If you can then yes try and straighten your back. To do this you need to bend from the hips rather than the waist. If you are tall or find it uncomfortable you may want to bend both legs as well. Don't worry too much about why you are putting side on but concentrate on cueing straight. Get used to finding the middle of the white and cueing straight through.