I have created more than a hundred of sketches on the P5js web editor.
Wanted to ask if there is some kind of folder structure which i can used within the web editor to organise the sketches.
Otherwise I will need to rename them with some kind of number system to organise by sorting.
Welcome to the forum 
Since the files are stored on the web server the folder structure is not accessible to the user instead you can create ‘categories’ in the same way this forum does and then organize your sketches into categories.
This has one advantage in that a sketch can appear in more than one category. Unfortunately navigating the sketches is slow and laborious process and it would be nice to have a tree type structure based on the categories.