Retrieve data from SP inside of From - stored-procedures

Question

I would like to use [sp_Test] to retrieve the data from the syntax code "FROM" but it does not work. Do you know how to solve it?
Thanks!
create table datatable (id int,
name varchar(100),
email varchar(10),
phone varchar(10),
cellphone varchar(10),
none varchar(10)
);
insert into datatable values
(1, 'productname', 'A', 'A', 'A', 'A'),
(2, 'cost', '20', 'A', 'A', 'A'),
(3, 'active', 'Y', 'A', 'A', 'A');
insert into datatable values
(4, 'productname', 'A', 'A', 'A', 'A'),
(5, 'cost', '20', 'A', 'A', 'A'),
(6, 'active', 'Y', 'A', 'A', 'A');
insert into datatable values
(7, 'productname', 'A', 'A', 'A', 'A'),
(8, 'cost', '20', 'A', 'A', 'A'),
(9, 'active', 'Y', 'A', 'A', 'A');
CREATE PROCEDURE [sp_Test]
as
begin
set nocount on
SELECT a.name, a.email, a.phone
FROM datatable a
end

Answer 1

First you should never name your stored procedure with sp_ prefix. It is very bad habit and can collide with system stored procedures.
Second you cannot simply use SELECT FROM EXEC, but you can create temporary table/variable to hold result and query it like:
DECLARE #t AS TABLE ( name varchar(100),
email varchar(10),
phone varchar(10));
INSERT INTO #t
EXEC [dbo].[sp_Test];
SELECT *
FROM #t;
SqlFiddleDemo
There is also workaround using loopback linked server and OPENQUERY:
SELECT *
FROM OPENQUERY(LOCALSERVER, 'EXEC [sp_Test]');
I strongly recommend to read:
How to Share Data between Stored Procedures
Why is selecting from stored procedure not supported in relational databases?.