Php learning has encountered problems

Php learning has encountered problems. now I can log on, post, add articles, message boards, upload pictures, and other basic functions connected to the database. I understand some basic principles, such as what session, within the cookie. Now I have some doubts: for my current foundation, how can I continue to learn php ??? Is using the php Manual to back up the function? Or how to learn it ?, Brother, I am also learning php on my own.
Now, I can log on, post, add articles, message boards, upload images, and other basic functions to connect to the database. I understand some basic principles such as what session, which is within the cookie.

Now I have some doubts: for my current foundation, how can I continue to learn php ??? Is using the php Manual to back up the function? Or how to learn it?

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Brother, I am also studying PHP by myself. the level is similar to yours, maybe it's better than yours.
I saw a PHP open-source website on the internet. it looks like that thing is quite good.
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I still think that the best way to learn is practice ~