To chat you have to sign up for an account, and yes its safe.. we still all have our identities.
Once you get into the chat, if you wanna join and play all you have to do is click on an open box and you'll be put in. If you just want to listen and enjoy you have to unmute everyone, you can either do this by clicking mute all and then unmute all.. or individually clicking on ppl's video boxes and unclicking the mute button.