Question: how install ttf in linux?
Answer: Step 1: Download the TTF font files. In my case, I downloaded the Hack v3 ZIP archive. ... 
Step 2: Copy TTF files into local fonts directory. First you're going to have to create it in your own homedir: ... 
Step 3: Refresh fonts cache with fc-cache command. Just run the fc-cache command like this: ... 
Step 4: Review available fonts.