how czn i update my computer
Well, that depends on what you want to update, which model Macbook Pro you have and which version os you are using, how much ram you have, the size of your harddrive, etc.
If you're asking how to update Apple software, typically you would use Software Update. You can get to this by clicking on the apple on the left of the menu bar.
If you're asking how to update something else, please be more specific.
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