If you just want a small section of it, use 'snipping tool' (on a PC), or 'screenshot' (on a Mac).
One or the other of these will be on your computer.
Use it to crop a small section a bit bigger than just the bit you want looked at, so that the handwriting of this particular person can be viewed.
That should create an image less than 500 kbs - the maximum you're allowed on here.
If it's more, go to 'Save as' and see if you can save it at a slightly less 'quality' - this will bring the file size down, but get it as near to 500 kbs as you can for clarity.