Hey Srinivas, 63 is a considerable score in GATE in Mechanical engineering but is not that good.

If you are from general category then your expected GATE score about 600 to 700 which I have calculated using the careers360s college predictor tool.

Refer to the link for using it:

https://engineering.careers360.com/gate-score-predictor

If we consider the previous year cut offs of various PSUs then there are very fewer chances of yours to get an interview call if you are from general category.

You can refer to the link below for the previous year cut offs for various PSUs:

https://engineering.careers360.com/articles/what-are-gate-scores-for-psu-recruitment

Hope this helps.