Why a font appears different in Mac Os and Windows


I have a font that appears differently in one OS than another.
In windows appears bold and in Mac Os, appears Regular font, although both have the same “Font family”.


Thanks Roel,

So a solution could be to add .TTF font to fonts directory?
Should it be named exactly as the font?
When I do F12 Developer mode, it looks like it had the font, but really it doesn’t.

How could I be certain the font is being applied correctly?