GrapheneOs is a very very good Os for phones, i think the level of privacy that this Os will give you is higher than Lineage. Maybe the only bad things is that you can istall it only on google pixell phones but it's not that big problem if you think at the positive sides that you have with a small ammount of money. I've read somewhere that you can already buy phones with GrapheneOs but don't do that, it sounds not so a safe thing, do things by yourself is always the best option.
What do you mean by talk? If you are asking wich are the best apps for communicate with others I'll say session and jabber.