Yes it is possible but switching from Rx 480 to gtx 1060 isn't going to make a big difference cuz there is not a big difference in performance between these two gpus you can only get 3 to 4 fps more that's it which is not worth upgrading. If you really need to upgrade then go with gtx 1070, it will give you much better performance. You have a decent psu which can handle gtx 1060 gtx 1070 and even gtx 1080 these cards require only 450 to 500 watts.
RX480 will outperform GTX1060 in some games and overall there is negligible difference, so I wouldn't recommend changing, you really want to be looking at an RTX2060/2070 if you are going to upgrade. Do you know what make and model of PSU you have? There is a huge variability in quality and you don't want to be sinking £400-500 on a new GPU if you're existing PSU isn't up to the job and prebuilts often have cheaper, poor quality PSUs so I would definitely recommend checking.