I see no deposit button on MetaMask?

My MetaMask Firefox extension does not offer a Deposit Button?
How is a deposit accomplished??
I do not need to buy, I own one ETH already.

Welcome to the MetaMask community. Are you looking for ways to transfer the ETH to your MetaMask wallet?
This article would be very helpful https://metamask.zendesk.com/hc/en-us/articles/360028141672-Direct-deposit-receive-tokens-to-your-MetaMask-wallet