Secure Encrypted Chatting Platform Development

This is a chatting website I called "Encrypted". It's a project I've spent less then 24 hours working on.

Is it fully secured? Not yet due to this only being a project to display to you so you can understand somewhat of what I can do.

It's coded in php, html and js. Backend is PY and PHP.

WHAT DOES IT DO?
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When you add someone and send them a message, platform takes that message and turns it into strings/random letters which are then added to the database(This way the messages can't be read unless it is sent to you) The platform then reads the database, takes the encrypted message and decrypts it which then shows a regular message such as "Hey".

Encrypted: Hekw4n@j4ke,s/sekOEl
Decrypted: How are you?
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I call the encryption "egg-plant-void-string".

The platform has a built-in adding function, like Facebook or Kik. You add a friend, message them, so forth. Nothing fancy, just a simple chatting platform with built in encryption, no money spent.

This was a big project for me because it shows I'm able to build something useful, secured (message wise). In the future ill show further updates such as encrypting account credentials so no data-breaches happen and more.

You only use a username and password to login/signup, no email, number or such needed.
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