Can I leave my $MLC on the Dashboard or do I have to claim them in my wallet?

The choice is entirely yours. They are safe on the dashboard.

Once claimed, they will both appear in your wallet and in the "MLC in connected wallet" section on your dashboard.

You can only manage them and use them once claimed in your wallet.

Please, remember to add the MLC to your wallet so they are visible.

Here's the tutorial to do so:

https://whitepaper.mylovelyplanet.org/lovely-family-mlc-investors/view-your-usdmlc-on-metamask