Now it's been 3 days I am using Mapinfo and it has Y as latitude and X as longitude. Is that the same case for all mapping software? As for any country their respective value is multiple of 1 or -1. So for Nepal can I say it is on positive side +1 for both latitude and longitude? And for USA to be +1 Y and -1 X.
No, for example when talking to a GeoServer WFS (or any other compliant WFS) the axis order depends on if you ask for version 1.0 or 1.1 of the spec in EPSG:4326.