get all columns from table sql

SELECT *
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE TABLE_NAME = N'Customers' 
-- INFORMATION_SCHEMA is an ANSI-standard (American National Standard Institute) set of read-only views which provide information about all of the tables, views, columns, and procedures in a database
-- "N" defines the subsequent string (the string after the N) as being in unicode

SELECT
  	TABLE_NAME
FROM
  	INFORMATION_SCHEMA.TABLES

/* To retreive the column names of table using COLUMN_NAME */
SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = N'table_name_here'

SELECT *
FROM INFORMATION_SCHEMA.COLUMNS -- INFORMATION_SCHEMA is an ANSI-standard (American National Standard Institute) set of read-only views which provide information about all of the tables, views, columns, and procedures in a database
WHERE TABLE_NAME = N'Customers' -- "N" defines the subsequent string (the string after the N) as being in unicode