Bootstrap means

what does it means by bootstrap
and form where i linked it ?

Bootstrap is a framework which helps you with designing your page.
There are a lot of buttons, forms, grids and much else already designed for you and free
to use, you just have to implement bootstrap first into your page via

There you get a proper introduction into it + the link you need to implement it

thx , the problem that I copy the code to my PC and try to run but does’t give me the same result ?

have u added

<link rel="stylesheet" href="" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">

to your head element?
otherwise, your browser does not know where to look for the classes you´re using

thanks, i am very grateful