I'd like to be able to allow a user to select an image from their computer and my program will resize it so that it fits within a certain range. In many social media apps, you have a frame so you can select a part of the image that will become your profile image. I want to do something similar but I don't know where to start. Could anyone give me any assistance in what I should be thinking about or where to look for information. I'm currently learning javascript and php so preferably in those languages
You don't need to do it on the server in PHP. You can do it on the client, in just Javascript.
Try these out:
https://www.liip.ch/en/blog/resizing-images-with-javascript
https://imagekit.io/blog/how-to-resize-image-in-javascript/
https://codesalad.dev/blog/how-to-resize-an-image-in-10-lines-of-javascript-29
If you have problems, come back and ask here, showing what you tried and what problems you faced.
Ideally use the "<>" icon to paste in exactly the code you wrote, so we can replicate your problem.