For Website you can use 'Roboto' font as below:
If you have created separate css file then put below line at the top of css file as:
@import url('https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,500,500i,700,700i,900,900i');
Or if you don't want to create separate file then add above line in between <style>...</style>:
<style>
@import url('https://fonts.googleapis.com/css?
family=Roboto:300,300i,400,400i,500,500i,700,700i,900,900i');
</style>
then:
html, body {
font-family: 'Roboto', sans-serif;
}