How do I add Ethereum mainnet to metamask?

At the top left corner of the MetaMask interface, select “Ethereum Mainnet” to drop down the menu, then click the “Add Network” button. Add Network With MetaMask

How to connect metamask to Ethereum mainnet (ETH) Dapps?

As mentioned earlier, MetaMask is used to connect with the Ethereum blockchain. But to connect MetaMask to the Ethereum Mainnet (ETH) DApps, certain settings need to be changed so that the wallet is focused on the nodes of the Ethereum Mainnet (ETH) network. To add Ethereum Mainnet (ETH) manually, click "Add Network" in the upper-right corner.

Can I use metamask on any Ethereum-compatible network?

Instead, MetaMask keeps a list of the most popular tokens, and automatically detects those; but no worries, if you get one that's less common, you can easily add it manually. Here's the really incredible part — you can use MetaMask on any Ethereum-compatible network, with any Ethereum-compatible token, following the same process. Why?