Student or Learner
I am bit confused by the use of articles.
What should we used with countable nouns and uncountable nouns?
Tedmc, "I am a bit confused by ..." is correct.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.
You can use indefinite and definite articles as well as none with countable nouns. With uncountable nouns, you can use the definite article or none.
Usually, but I would always hesitate before saying only.