How to swap core on MetaMask?

Can you explain in detail the process of swapping CORE tokens on MetaMask? As a crypto user, I'm interested in understanding the steps I need to take to securely and efficiently trade my CORE tokens. Could you please guide me through the entire process, including any precautions I should take to ensure the safety of my funds? I'm also curious if there are any fees associated with the swap, and if so, how they are calculated.