How does neutralization reaction differ from using a buffer?

Hint: The pH is the main factor used to differentiate between the neutralization reaction and the buffer solution. In neutralization reaction, salt is formed by reaction acid with the base whereas the buffer solution is prepared by mixing weak acid and its conjugate base and vice versa.

Complete step by step answer:
The neutralization reaction is defined as the reaction which takes place between the acid and the base which results in the formation of a salt by eliminating water as the by-product.
The general neutralization reaction is shown below.
$Acid + Base \to Salt + water$
The pH of the salt is usually 7.
The buffer solution is a water solvent which is prepared by the mixture containing a weak acid and the conjugate base of the weak acid or a weak base and the conjugate acid of the weak base. The property of the buffer solution is that it resists any change in pH when any small amount of acid and base is added.
The difference between the neutralization reaction and the buffer solution is that the pH of the product of neutralization reaction (salt) changes frequently on adding any small amount of acid or base whereas the pH of the buffer solution does not change or show minimal change when a small quantity of acid or base is added.

Note:
You must know that the buffer solution can be formed by adding a strong base to the solution of weak acid to neutralize half of the weak acid to its conjugate base example converting half of the concentration of acetic acid to its conjugate base acetate ion. Also, buffer solution can be prepared by adding strong acid to a solution of weak base in order to neutralize half the concentration to its conjugate acid. Example weak base ammonia neutralized to its conjugate acid ammonium ion.