It is possible to score good rank in GATE 2017 with job?

You can definitely do it. But you need to be disciplined enough to come and open books or study even after having a tiring day in office or get up early in the morning around 4.00 and study before going to office. If you follow this routine for at least 3 months and 3 hrs per day that's good enough preparation to get into IITs. All the best.