I've been working in my first website but I just want now what I need to do to make it work properly in all browsers.

Question

I am talking about smartphone and pc Browsers...

Answer 1

It can be very difficult to get a website to function exactly the same across every browser on every platform. Most developers will test on the most popular browsers first. A web search will give you a list of usage statistics on browsers. For PC, you can install virtual machines with virtualization software like VirtualBox, and create a snapshot of different operating systems with different browser versions. I used to do this for every version of Internet Explorer.

There are also browser extensions and device emulators that you can use to test your site with different display resolutions and aspect ratios for tablets, smartphones etc., but they're never as good as testing on a real device.

That being said, you can go to IRC channels for web development and find people willing to test your site on their devices. Just be willing to do the same for them.