https://cannigma.com/where-cannabis-is-legal-in-europe/
This is the most exhaustive site I could find on the subject, as legislation evolves quite rapidly. Other maps I found were from a few years ago and didn't take into account recent developments.
As a side-note, the European Commission decided to partially register a European Citizens' Initiative on Cannabis a few days ago:
https://ec.europa.eu/commission/presscorner/detail/en/ip_24_650
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