Well, there are some opensource implementation of VPN software you can simple deploy on your own server. So you do not need to code your own software but you need to trust to developer of specific software, of course.
Generally speaking, more and more it's becoming philosophical question. IMHO there is nothing surprising about that. If you don't trust to service provider, you cannot trust that service will be private. If you don't trust to developer of a program or even operating system, you cannot consider your working environment as private. If you cannot trust to computer hardware manufacturer, you cannot treat your computer as private. Simple, isn't it?
Probably you are not capable of creating own computer hardware and code your own software so you have to trust to somebody who have done those things for you. Thats how it works. Back to topic - if you live in a country with stupid laws so you cannot trust to connection provider because he is bonded by laws of country he operates in, the VPN provider from other country without specific stupid laws you care about can be considered as private augmentation. It's all about personal priorities.
I will study more about this topic because I find it interesting and important these days!
By the way, a silly question, for example, if a certain person is committing a crime, (money laundering).
He's already being investigated, can there be a court order and breach of confidentiality in these VPN companies and encrypted email companies?
Can the police act to carry out an investigation and breach of confidentiality in these VPN and encrypted email companies? Is this possible?
This is hard to answer. Ask a specific provider and trust his answer. You have to count with simple fact, that provider have to (and will) cooperate with law enforcement organizations of country he operates in. Some of them declarates that it is impossible (kind of personal key is stored only localy on your computer, do not stores logs at all, etc) - but you have no guarantee that it is truly like that, maybe just because of some bug in software, even in some third-party lib for example.
That's why it is good idea of decentralization (in anything), E2E encryption, using OSS software, do not rely to only single security layer, etc etc... And of course - if you do not understand to technical backend, you cannot decide who to trust at all.