if there any possible to delete single entity using TRUNCATE in sql

If by "single entity" you mean a single row then the answer is "No" - you cannot use Truncate in sql to do that - see the Documentation[^] for Truncate

Quote:

Removes all rows from a table without logging the individual row deletions. TRUNCATE TABLE is similar to the DELETE statement with no WHERE clause; however, TRUNCATE TABLE is faster and uses fewer system and transaction log resources.

If you have the means of identifying which row you want to remove then include those details in a WHERE clause e.g.

DELETE FROM tablename WHERE ID=7

or

DELETE FROM tablename where column1 = 'A' and column2 = '2'

or however you know which row to delete.

If by "single entity" you mean a table then the answer is still "No" - the table will still exist but will be empty (refer to documentation link above).
In that instance you will need to use DROP TABLE[^]. E.g.

IF OBJECT_ID(N'dbo.tablename', N'U') IS NOT NULL
    DROP TABLE dbo.tablename;

or

IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[tablename]') AND TYPE IN (N'U'))
DROP TABLE [dbo].[tablename]