@jt_rebelo Signal is the way to go. Right now. Today.
Telegram - just no
Teams - yes if you are part of an Office365 entity and need logging
WhatsApp - not unless you want law enforcement read everything you tap given Androids decision making around write records and notification logging in the clear.
Signal - today - at this time - is the sole messaging platform you should use.
Email: IT DOESN'T MATTER, if you email anything assume it's compromised the minute you pressed send.