Will you please explain, why Carbonic acid gives an ACID SALT but Hydrochloric acid doesn't???HCL, HNO3, C2H6OH, C6H12O6 all contain H atom but only HCL and HNO3 show ACIDIC CHARACTER, why??

Acid salts can be formed only with neutralization of diprotic or polyprotic acids. Hydrochloric acid has only one hydrogen atom that is displaced during the reaction and therefore hydrochloric acid salts are not acidic in nature. On the other hand carbonic acid is diprotic and on neutralization it still contains one hydrogen atom that can be displaced, therefore carbonic acid salts are acidic in nature.