Student or Learner
"The British education system is very flexible in order to provide for the needs of a modern, complex society."
More: BBC Learning English | News about Britain
Can I replace comma with conjunction and? This site says "Rule 2: Use a comma to separate two adjectives when the word and can be inserted between them."
In that instance, yes.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.