hello, i recently bought 200gb space in iCloud, and I'm uploading my entire photo library to it. There is 10,000 photos on my Mac book air. It is taking a long time, been running it 2 days now and seems to be only doing about 300photos per day/night.

It really will depend on the speed of your network. Best use a wired connection to your router and not the Wi_Fi.

If your upload speed is poor, it may indeed take a month.

It is taking a long time, been running it 2 days now and seems to be only doing about 300photos per day/night.

You may have items in your Photos Library that cannot upload. Is your Photos library in your Pictures folder or on an external drive? Are all photos stored inside the Photos Library, or did you disable the Photos Preference > General "Importing: Copy Items to the Photos Library"? If this option is disabled, the photos imported this way cannot upload to iCloud. And if Photos cannot find photos imported this way the upload to iCloud may hang.

You can search for photos that are not stored inside your library and may be problematic with a Smart Album:

File > New Smart Album: Photo is Referenced

Is this album empty, or are there referenced photos?

Other problematic items could be videos, that Photos cannot convert or image files, that are in a graphics format and not the usual JPEG, TIFF, PNG, ...