How can i create a page without adding .html?

Like dis => https://www.nairaland.com/nigeria

The name Nigeria is just a folder under the root of the main home page, inside that folder will be an index.html page or default.asp or something like that. So, if you want your home page to show up like that - create a folder under the main home page and keep your default or index file in there. In that way, you dont have to put the .html at the back. But remember - its just a folder name.

i 'll give it a try. Thanks.

google .htaccess

Well there are 2 ways.
1- Htaccess go and google up HTACCES
2- Using a php framework. Not necessary a big framework a minimalistic framework will do.

Also nairaland is not under a folder call nigeria. Nairaland uses what is called php path info to detect uri. Now d nairaland.com/index.php/topic-3286.html d index.php side has been renamed to nigeria. Thats why u see it such way. If u are using an smf forum then go search pretty smf mod. U will see a plugin that will do all this for u and even make your topic title in the url instead of numbers.
Am off

Search google for "dhtml create site without showing .php" that should show you a solution i made for php, it might work for hml, if it doesnt contact me directly.