Can my employer make me shave my beard off
The short answer to this is yes. It is your employer’s business and therefore their rules unless a rule is clearly discriminatory and aimed at a certain group. For example, the Disney Store had a policy of not allowing staff to wear beards because in Disney movies the heroes were clean shaven and the villains wore beards. This is not aimed at a particular group and so is perfectly valid.
It may seem silly in this day and age but some people perceive beards as more scruffy-looking and casual so businesses ask employees to be clean-shaven to look professional.