How can I write procedures that I can loop over to insert a series of files into my database?

My goal: Insert a series of csv files into my database by creating procedures for each individual table and then looping over them. My csv files will all be named very similar to this: - 1_to_be_inserted_into_table_1 - 1_to_be_inserted_into_table_2 - 1_to_be_inserted_into_table_3 - 1_to_be_inserted_into_table_4 - 2_to_be_inserted_into_table_1 - 2_to_be_inserted_into_table_2 - 2_to_be_inserted_into_table_3 - 2_to_be_inserted_into_table_4 - 3_to_be_inserted_into_table_1 - 3_to_be_inserted_into_table_2 - 3_to_be_inserted_into_table_3 - 3_to_be_inserted_into_table_4 This is the pseudocode for the final loop where I'd like to reference all of my procedures:

CREATE OR REPLACE DIRECTORY all_the_data AS 'D:\Favorites\1. Programming\Projects\LYS_database\DATA TO INPUT';

DECLARE @file_selector INT
SET @file_selector=1
    
BEGIN
    FOR files IN all_the_data LOOP 
        
        EXEC procedure_1 ((file_selector || 'to_be_inserted_into_table_1'|| '.csv')),
        EXEC procedure_2 ((file_selector || 'to_be_inserted_into_table_2'|| '.csv')),
        EXEC procedure_3 ((file_selector || 'to_be_inserted_into_table_3'|| '.csv')),
        EXEC procedure_4 ((file_selector || 'to_be_inserted_into_table_4'|| '.csv')),
        
    SET @file_selector= file_selector+1
    commit;

END;
/

QUESTION 1: What am I doing wrong with creating the procedure below? It worked perfectly fine to insert data into a table before I tried to make it a procedure.

CREATE OR REPLACE PROCEDURE INSERT_CPP 
    (file_name IN varchar2)

IS
    cpp_data VARCHAR(200) := 'D:\Favorites\1. Programming\Projects\LYS_database';

BEGIN
    insert into cpp
    SELECT * FROM EXTERNAL (
        (
      cpp VARCHAR2 (50),
      rfu1 NUMBER (6, 2),
      rfu2 NUMBER (6, 2),
      mean_rfu NUMBER (6, 2),
      charge_ph7_4 NUMBER (2),
      hydropathy NUMBER (3, 1))
    
        TYPE ORACLE_LOADER
        DEFAULT DIRECTORY (" || cpp_data || ")
        ACCESS PARAMETERS (
            RECORDS DELIMITED BY NEWLINE
            skip 1
            badfile (' || cpp_data || '\badflie_cpp.bad')
            FIELDS TERMINATED BY ','
            MISSING FIELD VALUES ARE NULL 
            ) 
        LOCATION (file_name)
        REJECT LIMIT UNLIMITED) ext
        where not exists (
            select * from cpp c
            where c.cpp = ext.cpp );
END;
/

I get an error:

5/5       PL/SQL: SQL Statement ignored
16/27     PL/SQL: ORA-00922: missing or invalid option
30/1      PLS-00103: Encountered the symbol "end-of-file" when expecting one of the following:     ;

QUESTION 2. Is there a way to write a

files IN all_the_data LOOP

in SQL? I tried this solution but the code from the first step wasn't recognized as a command. I did

EXEC sp_configure 'show advanced options', 1

RECONFIGURE

and got

RECONFIGURE
Error report -
Unknown Command

QUESTION 3. Can i write

;

at the end of every loop so that if something goes wrong on the very last file it doesn't rollback everything? Will that work?