Unfortunately, there is no option to delete all posts On Instagram. If you want to get rid of everything you've ever posted on this platform, you will either need to continue doing this to each and every one of your posts.
with the help of this extension, you can delete all your posts on youtube without having to bother with manual clicks one by one. this script will do it, you just press the start button and you can let the computer work for you.
How to use and Demo : https://www.youtube.com/watch?v=p5NsbTlxC3k
I really hope for your support by subscribing to my youtube channel : https://www.youtube.com/channel/UCqRqvw9n7Lrh79x3dRDOkDg
note: The extension may not work in the future if instagram changes their layout, in this case, you should subscribe to my channel to get an update for the new script.