As some of you understood I'm new on oracle

I need to do an insert, I want to copy the data of a table A from a schema X to another table A on a schema Y

The structure of the tables is the same.

something like
insert into Table Y.A values
(select * from Table X.A)

Hi Urian,
use

insert into shema_A.table_X
(select * from schema_B.table_Y)

Thanks a lot.

This assumes the target table already exists in A.

To create the table in A from B with no data (add a condition that cannot be met):
create table A.X as select * from B.X
where 1=2;

Or, to create and insert/populate at the same time, omit the where clause:
create table A.X as select * from B.X;

" I want to copy the data of a table A from a schema X to another table A on a schema Y"

Use Create Tbale as Select (CTAS)

http://www.dba-oracle.com/t_create_table_select_ctas.htm