How can I set top left corner to have (0,0) coordinates in Inkscape?
You can't. There's an ongoing change to address this an additional work on making it user-configurably. https://bugs.launchpad.net/inkscape/+bug/170049
It's targetted to the 0.49 release so perhaps if you try a "nightly" it'll have what you're after?
In Inkscape 1.0 the coordinate system is reversed, so that the top left corner is (0, 0) by default.
You can download the beta version from the official site, or install it with snap:
snap install inkscape --edge