Counting and grouping in hierarchy (Sqlite)?

Question

SQL

There are 2 tables.
1st is a hierarchical structure and looks like this:
code | parent | level
001 | | 1
001.1 | 001 | 2
001.1.1 | 001.1 | 3
001.2 | 001 | 2001.3
| 001 | 2
2nd contains articles and column code (refers to the 1st table)
I want to display the codes of the 2nd level and the number of articles with the corresponding codes, so that the articles of all child codes are taken into account in the calculation.
I understand that you need to use WITH, GROUP BY and probably JOIN. I try, but something does not work out
Thank you.