Hello there,
I want to create ligatures for fb fh fk but I can’t find the Unicode numbers. Do they have? Or else, what is the best way to place them in my Glyphs font.
They do not have a Unicode code point. (The fact that fl and some other ligatures have code points is for historical reasons.)
See the Ligatures tutorial for a guide on building custom ligatures:
Oké, That’s clear. 
Thank you.