Need script to extract text at certain places in a set of .txt files... (regEx) ?

I need a small script that uses regular expressions (egrep) or something similar to extract small pieces of information from .txt files, and put this info in a new comma separated .txt. Like this:

1. User put into script the number of iterations to loop (into the code). From A to B. The iterations is the same as the number of files to process.

2. In a set directory, the .txt files have prefixes [001_, 002_ etc]. Script loads the first file.

3. Script checks the FIRST row for a match of [ N], and extract the part between the “ ” before “N” and the previous “ ” on that row. (Example: 00 4430.7486 N 06417.4951 W). If no match, then script instead check on that FIRST row a match of [,”N”] and extract the part between the “,” before “N” and the previous “,” on that row. (Example: 0,4430.7483,"N",6417.4969,"W")

4. Script checks the FIRST row for a match of [ W], and extract the part between the “ ” before “W” and the previous “ ” on that row. (Example: 00 4430.7486 N 06417.4951 W). If no match, then script instead check on that FIRST row a match of [,”W”] and extract the part between the “,” before “W” and the previous “,” on that row. (Example: 0,4430.7483,"N",6417.4969,"W")

5. Script does the same thing as on 3 above, but for the LAST row in the current .txt file.

6. Script does the same thing as on 4 above, but for the LAST row in the current .txt file.

7. Script creates a new .txt file with: loop iteration number, Extraction in 3, Exctraction in 4, Extraction in 5, Extraction in 6. (Example: 001, 4413.7896, 6413.7896, 4412.1256, 6415.2223)

8. Script starts over with next iteration in loop, loads a new .txt file and write a new row in the created .txt file for each round.

Could someone help me with this ? It for a hobby project.