Sizing help! what does this mean!?

Okay im trying to resize pics that i took it has to be

There's a maximum size: Your image needs to be under 800k and 4 million total pixels.

And there's a minimum size: It needs to be at least 7kb. Also the image needs to be bigger than 200 width and 300 height.

how do i do this?

4 million pixels is an image no bigger than 2000 x 2000 pixels eg 2000x2000 = 4,000,0000. Or variations thereof.

If the 800k is a problem then compress the file when saving it (but you will lose quality) by doing File -> Save for Web, save as jpeg, minimum quality 80 unless you want a really rubbish image. If you get any warnings about file being too large for the internet, ignore them.

I presume you know how to use Image -> Resize -> Image Size....