EMail isn't really a good idea if you need truly secure communications.
Proton is easy to use, has most features most people want, and is decent for most threat models (especially if all parties to an email are on Proton). For 99% of people and use cases, it is a good default email provider.
Tuta is somewhat better from a security & privacy perspective but in every other respect it tends to lag behind Proton. Still, its a solid option.
In either case, short of a targeted effort from a major NatSec actor you are going to be just fine unless you were stupid (recovery email or phone are the big ones).