Connect into mysql from terminal

$ sudo mysql -u root -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 25680
Server version: 10.3.22-MariaDB-1ubuntu1 Ubuntu 20.04

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| blk_wpdb           |
+--------------------+

Then select from the wp_users field

MariaDB [(none)]> use blk_wpdb;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
MariaDB [blk_wpdb]> show tables;
+-------------------------------------------------+
| Tables_in_blk_wpdb                              |
+-------------------------------------------------+
| wp_commentmeta                                  |
| wp_comments                                     |
| wp_et_bloom_stats                               |


     [ shortened for security purposes ]


| wp_usermeta                                     |
| wp_users                                        |
+-------------------------------------------------+
48 rows in set (0.001 sec)

MariaDB [blk_wpdb]> SELECT ID, user_login, user_pass FROM wp_users;
+----+----------------+------------------------------------+
| ID | user_login     | user_pass                          |
+----+----------------+------------------------------------+
|  1 | wp-admin       | $Z$BDoTAnbhsiwkIOHNKJhinlZ1MTy/nz0 |
+----+----------------+------------------------------------+
1 row in set (0.001 sec)

This is where the magic happens, just enter the new password as such

MariaDB [blk_wpdb]> SELECT ID, user_login, user_pass FROM wp_users;
+----+----------------+------------------------------------+
| ID | user_login     | user_pass                          |
+----+----------------+------------------------------------+
|  1 | wp-admin | $Z$BDoTAnbhsiwkIOHNKJhinlZ1MTy/nz0       |
+----+----------------+------------------------------------+
1 row in set (0.001 sec)

MariaDB [blk_wpdb]> UPDATE wp_users SET user_pass = MD5('newpassword_here') WHERE ID = 1;
Query OK, 1 row affected (0.041 sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [blk_wpdb]>