Well you didn't really specify which model PSU it is, but It's likely that it'll work fine since plenty of RX 560's and GTX 1050 (Ti's) don't even need a PCIe connector from the PSU to run. You just plug them into the PCIe slot and they work, but pay attention if this is the case for the GPU you're buying.
If you can, get the GTX 1050 Ti. That's the best performer below 20K INR. Otherwise you have to look at either the RX 560 and GTX 1050 which are really similar to each other in performance.