Fuente para el código CSS Google Link
@import url(https://fonts.googleapis.com/css?family=Open+Sans);
body{
font-family: 'Open Sans',serif;
}
Handsome Hamster
@import url(https://fonts.googleapis.com/css?family=Open+Sans);
body{
font-family: 'Open Sans',serif;
}<!-- To Add Montserrat font or any font as such -->
<!-- Go to https://fonts.google.com browse the font you like here, Montserrat-->
<!-- On the right click embbed and get the link similar to one given below-->
<link href="https://fonts.googleapis.com/css2?family=Montserrat&display=swap" rel="stylesheet">
<!-- add this ^ link inside your <head> tag i.e. before </head> -->
<!-- In css you can specify the font family as -->
font-family: "Montserrat", sans-serif;