Is using an Matrix account from matrix.org private and secure enough to talk with my family members and people in general?
So, I was told to not use Signal, so all that is left is Matrix. And I am not techy enough to have my own server and neither are my relatives, so Matrix.org is the only option
Yeah, sure. But Matrix is decentralized and federated. So you can pretty much join any instance and be able to talk with anyone on any instance. So why not select another instance or maybe even self host one yourself?