SQL Server: how to print all the column names of a query output

How to print all the column names of a query output ?

DECLARE @Fields as NVARCHAR(3000)
set @Fields = ''SELECT @Fields = @Fields + ', ' + COLUMN_NAME FROM .INFORMATION_SCHEMA.COLUMNS
where Table_Name = 'Employee'

print SUBSTRING(@Fields, 3, len(@Fields))

–OutPut
–emp_id, emp_name, emp_age, emp_salary

how to return multiple rows of a query output as one string?

DECLARE @SingleLine varchar(100)
SELECT top 10 @SingleLine = COALESCE(@EmployeeList + ', ', '') +
CAST(account_num AS varchar(5))
FROM cl_accountSELECT @SingleLine

--OutPut
--*, 70, 71, 72, 73, 74, 75, 76, 77, 78