SQL> create or replace procedure test_receive(t_var1 in number, t_var2 out number)
  2  as
  3  begin
  4  t_var2:= t_var1*10;
  5  end;
  6  /

Procedure created.

SQL> create or replace procedure test_send(proc_name varchar2)
  2  as
  3  t_var3 number;
  4  begin
  5  EXECUTE IMMEDIATE 'CALL "' || proc_name || '" (t_var1,:t_var2)' using 5,t_var3;
  6  dbms_output.put_line(t_var3);
  7  end;
  8  /

Procedure created.

SQL> exec test_send('test_receive')
BEGIN test_send('test_receive'); END;

*
ERROR at line 1:
ORA-01006: bind variable does not exist
ORA-06512: at "MICHEL.TEST_SEND", line 5
ORA-06512: at line 1


SQL> create or replace procedure test_send(proc_name varchar2)
  2  as
  3  t_var3 number;
  4  begin
  5  EXECUTE IMMEDIATE 'CALL "' || proc_name || '" (:t_var1,:t_var2)' using 5,t_var3;
  6  dbms_output.put_line(t_var3);
  7  end;
  8  /

Procedure created.

SQL> exec test_send('test_receive')
BEGIN test_send('test_receive'); END;

*
ERROR at line 1:
ORA-06576: not a valid function or procedure name
ORA-06512: at "MICHEL.TEST_SEND", line 5
ORA-06512: at line 1


SQL> exec test_send('TEST_RECEIVE')
BEGIN test_send('TEST_RECEIVE'); END;

*
ERROR at line 1:
ORA-06536: IN bind variable bound to an OUT position
ORA-06512: at "MICHEL.TEST_SEND", line 5
ORA-06512: at line 1

SQL> create or replace procedure test_send(proc_name varchar2)
  2  as
  3  t_var3 number;
  4  begin
  5  EXECUTE IMMEDIATE 'CALL "' || proc_name || '" (:t_var1,:t_var2)' using 5, out t_var3;
  6  dbms_output.put_line(t_var3);
  7  end;
  8  /

Procedure created.

SQL> exec test_send('TEST_RECEIVE')
50

PL/SQL procedure successfully completed.