It depends what you want
If all you need is zero access encryption then Tuta is fine but if you would like to use OpenPGP more like u did in Proton then maybe mailbox.org and posteo would be better choice imho
It depends what you want
If all you need is zero access encryption then Tuta is fine but if you would like to use OpenPGP more like u did in Proton then maybe mailbox.org and posteo would be better choice imho