Updating a column in PL/SQL - sql

Question

(Using PL/SQL anonymous program block)
I have a table tblROUTE2 of Mexican state highways:
+-----------------+------------+---------+----------+----------+----------------------------+-----------+--------+
| TYPE | ADMN_CLASS | TOLL_RD | RTE_NUM1 | RTE_NUM2 | STATEROUTE | LENGTH_KM | STATE |
+-----------------+------------+---------+----------+----------+----------------------------+-----------+--------+
| Paved Undivided | Federal | N | 81 | | Tamaulipas Federal Hwy 81 | 124.551 | NULL |
| Paved Undivided | Federal | N | 130 | | Hidalgo Federal Hwy 130 | 76.347 | NULL |
| Paved Undivided | Federal | N | 130 | | Mexico Federal Hwy 130 | 68.028 | NULL |
+-----------------+------------+---------+----------+----------+----------------------------+-----------+--------+
and tblSTATE2 of Mexican states:
+------+-----------------------+---------+-----------+
| CODE | NAME | POP1990 | AREA_SQMI |
+------+-----------------------+---------+-----------+
| MX02 | Baja California Norte | 1660855 | 28002.325 |
| MX03 | Baja California Sur | 317764 | 27898.191 |
| MX18 | Nayarit | 824643 | 10547.762 |
+------+-----------------------+---------+-----------+
I need to update the STATE field in tblROUTE2 with the CODE field found in tblSTATE2, based on the route name in tblROUTE2. Basically, I need to somehow take the first string or two (some routes have two names)-- before the string 'Federal'-- of the STATEROUTE field in tblROUTE2 and make sure it matches with the string in the NAME field in tblSTATE2. Then since the states are matched with a CODE, update those codes in the STATE field of tblROUTE2.
I have started a code:
DECLARE
state_code
tblROUTE2.STATE%TYPE;
state_name
tblSTATE2.NAME%TYPE;
BEGIN
SELECT STATE, NAME
INTO state_code
FROM tblROUTE2 r, tblSTATE2 s
WHERE STATEROUTE LIKE '%Federal';
END;
As well, I will need to remove the state name from the route name. For example, the string in STATEROUTE 'Tamaulipas Federal Hwy' becomes 'Federal Hwy'. I have started a code, not sure if it's right:
UPDATE tblROUTE2
SET STATEROUTE = TRIM(LEADING FROM 'Federal');

Answer 1

Using MERGE update :
MERGE INTO tblROUTE2 A
USING
(
SELECT CODE, NAME FROM tblSTATE2
) B
ON
(
upper(SUBSTR(A.STATEROUTE, 0, INSTR(UPPER(A.STATEROUTE), UPPER('FEDERAL'))-2)) = upper(B.NAME)
)
WHEN MATCHED THEN UPDATE
SET A.STATE = B.CODE;
Here in FIDDLE I've replicated your tables and added additional record where STATEROUTE matches one of the records in NAME. Although Fiddle return an error, I ran it in my Oracle DB, and one record was updated correctly as the following screenshot: