I downloaded steam onto my macbook and it won't open at all.

Are you running any anti-virus apps, cleaning apps, or third party security software which may be interfering with the normal operation of macOS? If you have any of these types of apps installed, then you should uninstall them by following the developer's instructions. You do not need any of these types of apps on a Mac plus they usually cause more problems than they solve and they impact system performance.

How long has it been since your laptop was restarted? Rebooting a computer can sometimes be an easy fix.

Do you have an Intel Mac or an M1 Mac?

grey146 wrote:

I have no clue what kind of mac I have

You can get this information (and the exact model of the Mac) by clicking the Apple menu and selecting "About This Mac".

I once had a similar issue with an Intel Mac where Gatekeeper would not process the request to allow a third party app to run. I even tried using the command line to get more information, but there was information about any errors. I even attempted to delete the Gatekeeper preference files with no change. I ended up performing a clean install of macOS to resolve the issue. A clean install destroys all data on the drive. You could try reinstalling macOS over top of itself which should preserve your data and apps, however, I highly recommend you have a good backup beforehand just to be safe.

I haven't used Steam on macOS in a really long time, so I will be unable to help you further, but maybe another more knowledgeable contributor will have some ideas.

You said you had downloaded.

Did you also run the Install? Just having the download on your computer will not be enough to make it work.

Same thing man but I am trying to get Steam Vr and it seems that Apple or Steam/Valve doesn't really support it kind of a bummer but oh well.