EncryptKeeper’s explanation is perfectly concise and informative if you have a cursory grasp of self hosting and networking.
If it’s not making sense to you, I would suggest revisiting some of the technical fundamentals of self-hosting, which admittedly is quite an advanced topic that most people don’t, and do not need to care about.
You would be equally well-served, perhaps more so (if you don’t really care about privacy or terms of service) by sticking to regular cloud services. The road to self-hosting is arduous and if done wrongly, causes you more harm than good. Especially if your technical foundation is not yet strong. Which your posts suggest is the case.
If it’s not Hannah Montana Linux, I don’t want to hear another word of this.