I don't know the difference Among the a and an pls tell me

Uses of A :- Before a singular countable noun beginning with a consonant. Ex :- a dog, a car etc.. Uses of An :- Before a singular countable noun beginning with a vowel. Ex :- an angle, an ant etc.. Uses of The :- Before the names of epics. scriptures, or newspapers. Ex :- The Ramayana etc Before the superlative degree. Ex :- The most precious gift etc Before the names of prizes, awards. Ex :- The Noble Prize etc Before the name of musical instruments. Ex :- The piano etc Before the names of rivers, seas and oceans.

the is used for a particular thing a is used for consonant sound an is used for vowel sound