Everyone already said you can have multiple addresses on Metamask, I also have 100 addresses on my metamask. You just need to do :
- Open Metamask
- Fill Password
- Click Profile
- Choose +Create Account
- Name your new wallet
- Then, click created
Walla, you already have a new address wallet in a single wallet.
I agree this is what came to my mind I have different addresses on my metamask if you really wanted to have multiple accounts you can just create a password manager with all the passphrase and the likes and just use those when logging in to metamask.