Can it be possible to install e/os in my samsung galaxy a31

/e/OS Devices Request a Device
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I just want to have e/os in my phone

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Not in the moment. It was shipped with Android 10 and there is no eOS Q available.
But you can try the eOS GSI. How to you will find here [Custom Build] eOS Q for Samsung S9+ star2lte -- new build Sept. 16th