Add extensions and rename files in subfolders all at once

[gaklimited]

https://imgur.com/a/XzgJEuS

If you check out the imgur link, the first image shows all the subfolders inside parent folder 'hbvhhbm'
and the second image shows what each of those subfolders contain.

Basically, I need to do 2 things all at once:
1. add extension '.jpg' to all those files
2. change numbering from 0,1,2,3... to 00,01,02,03...

I can easily do this in Bulk Rename Utility if I go to each subfolder (like 26017039-1586617596211) one at a time, but I have almost 7000+ subfolders like this in one parent folder called 'hbnhhbm'.

Is there any way to this all at once from the parent folder?

I think I've been very clear, but I could explain this how many ever times until I could find a solution.

Thanks in advance to anyone who replies!

[therube]

12:Filters -> Subfolders ?

[gaklimited]

12:Filters -> Subfolders ?

When I tick that it just adds '.jpg' at the end of the folder names (26017039-1586617596211.jpg) which is utterly useless...

[gaklimited]

Oh I'm sorry... I had to uncheck 'Folders' and then check 'Subfolders' in Filters(12)