You should use a VPN anywhere you'd prefer not to be identified and Tor if you really don't want to be identified, but that's not enough to decouple your account from your personal identity; you'd need to create a new account that you only use through Tor and be very careful with what you post, at the very least (I wrote a summary of my setup somewhere if you're interested, but it's probably a hassle for most people). With that said, if you're already openly communist, using Lemmygrad is unlikely to expose you to further danger