If you would like to create and manage multiple SubWallet accounts, you could do so simply by creating new accounts.
Click the round favicon icon at the top right of your wallet and hit Create new account. Then repeat the steps in Create an Account to create an additional Polkadot Native Wallet and/or Polkadot EVM Wallet.
Rename an Account
Step 1: Hit the vertical ellipsis icon on the top right corner right below the favicon icon, then choose Rename.
Step 2: Change your account name to whatever you want and hit Enter on your keyboard to save change.
Choose a Network
Step 1: On SubWallet Extension, click on the drop-down list at the top. You can either scroll down the list to pick your desired network or type the network's name on the Search bar. Apart from the first four relay chains Polkadot, Kusama, Westend Testnet and Rococo Testnet, all other networks are listed in alphabetical order.
Step 2: Click on the Copy icon to copy the wallet address for your selected network.
To acquire EVM addresses, select your EVM account and click on the Copy icon to copy the wallet address for your preferred network.