I have a 2011 27 inch Mac that is running High Sierra 10.13.6. What are my options to update?

macOS High Sierra - Technical Specifications - Highest this computer can go.

macOS Mojave - Technical Specifications - This computer is too old

If you're trying to upgrade the OS, none.

If you're trying to update other software, it varies, but you can't run anything which requires Mojave or newer on it.

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