Welcome to the hobby and to the boards
a couple of thoughts on pointing your scope, first make sure you can identify which object in the sky is Saturn. this shouldn't be too difficult, Saturn is one of the brighter objects in the sky. i have used planetarium apps before and they work pretty well when you manually direct them rather than relying on it being accurate when you point to the sky. find some reference points like the moon and bright stars like Antares (which is bright and orange) from there you should be able to have some confidence that you can find Saturn. then make sure your finder scope is aligned to the actual telescope, it can be adjusted while pointing at a known target like the moon. slew your telescope to point at Saturn, centre in your finder scope then look through your main scope. Also the GoTo function is never going to be perfect (at least it hasn't been for me) unless you have a high end mount and perfect calibration but it will get you 95% of the way. also, when looking at planets you generally need high magnification. in your scope with a 6mm eye piece, Saturn will still be small (although i would have thought you could see the rings), a barlow will help to magnify it and give you the views you are looking for, 650mm of FL is not really enough.
Happy hunting !