Khasrang: Per our director of software development:

Minimizing, at the very least, will remove all the whitespacing from your code, so there’s no way to minimize the file without serving up a modified version. Most minimizers will rename variables and functions too in order to save space.

There are lots of tools that will do this for you. Minifying and combining JS/CSS is a pretty common task. There is no magic “always works” tool since the tool you use will need to be compatible with any theme or template you’re using. There may also be some scripts you need to leave out of the minimizer (like jQuery) if lots of other scripts depend on it or it needs to be loaded before other items on the page.

Praveen: Certainly, creating resources that will best help your users should be your focus. Beyond that, many different factors influence ranking. We’ve written a lot about this on our website, but for specific help for your site, you may want to engage an experienced SEO agency.