Job portals and application forms love a 200 KB limit, and a modern phone photo is twenty times that. Here is the order of operations that gets you under it without wrecking the image.
Most people reach for a quality setting first and end up with a blotchy picture that is still too big. The trouble is that quality and file size have no fixed relationship: the setting that takes a plain headshot under the limit will leave a detailed outdoor photo at twice the size, because there is far more detail to throw away.
Giving the limit as the input removes the guessing. The quality becomes whatever satisfies the number, and the picture is only scaled down in pixels if quality alone cannot get there.
If you have the choice of format, WebP produces noticeably smaller files than JPG at the same visible quality. Plenty of older upload forms still refuse it, so if the form is fussy, stay on JPG and lean on the width.
The tool lowers the quality first, and only makes the picture smaller in pixels if lowering the quality is not enough. If the result looks soft, the cause is usually that the photo started out very large. Crop it tightly with Crop & rotate before you compress, because fewer pixels means less has to be thrown away to reach the limit.
A 600 by 800 pixel photo fits in 200 KB at good quality. If you only need it to be recognisable on a form, that is plenty. You can type any limit in kilobytes, not only the presets, so use the exact figure the form states.
Phone cameras shoot at a resolution meant for printing, not for uploading. Most of that detail is invisible on a screen.
Yes. Add as many as you like and they all get the same settings.
No. It is compressed by your own browser and never sent anywhere.
Yes. Tick the box saying the file also has to be at least a certain size and enter it. This is best effort, and it will never push the file over the maximum.