Main html file
PermalinkI need to add a new font. In Google fonts it's quite easy except the step where I have to copy a line in the head of the main html file.

It's best to forget how you used to build websites because nothing will make sense if you try to build your old way in concrete5.
What theme are you using?
Most themes have a header.php where you would add this code. Have a look in:
[root]/packages/your_theme/themes/your_theme/elements/header.php
or
[root]/themes/your_theme/elements/header.php
You might want to start your concrete5 journey here:
http://www.concrete5.org/documentation/recorded-trainings/theme-dev...
Mhawke: You got me! I'm Old School style...
Header.php is the one I was looking for.
I gave several possible locations for the header.php file because it's not always where you said it was and this is a confusing point for those just starting out with C5.
I gave a link to some documentation that might help him better understand how concrete5 works.
~ Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime ~