I’m sorry but your English is quite broken so I may not understand your question.
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Install a fresh copy of Raspbian from the first link I gave you.
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Install HA Venv from the second link I gave you.
Is that what you did.
It is maybe because I’m French 
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Yes it is what I did.
To simplify my questions, can you tell me if these statement are true :
- Raspbian OS lite is install on the SD card that used for the set up of the raspberry
-if I retire this SD card, is there no OS in my Raspberry ?
The OS is stored on the SD card,not on the Raspberry Pi. Put a new OS on the SD card, insert the SD card et voila the Pi has a OS.
With a venv you can’t install add-ons, it’s not hard, it’s impossible! Add-on are docker container that provide some additional functionality, e.g. there’s an add-on to create a samba share, with the add-on you install it through the UI, set some config parameters and you’re done, with the venv you need to install and configure samba yourself. Samba is easy, but there may be other add-on that are not so easy to replicate in a venv.
If you install HA supervised on top of the Rasbian lite OS, you get the add-ons and can still use your Pi for other things as well.