Student or Learner
WHAT IS DIFFERENCE BETWEEN MINIMUM AND MINIMAL
you can find it in the dictionnary (for example: Cambridge Dictionary Online),
one of the two words can be an adjective or a noun and the other is only one adjective.
Abou the meaning I think mimimun is less bigger than minimal, but it's my mind.
Have a nice day.
The usage is slightly different. For example, you might say, "He succeeded using minimal (not minimum) effort. Or, you might say (for example), "I think you should give a minimum of ten dollars." I think minimal is more likely to be used as an adjective than minimum. (But I could be wrong.)