Custom blocks not showing

Hello i’m still learning how to create custom blocks by following the handbook, but after i follow the guide and activate the plugins, it’s still not showing on my blocks list.

I’ve tried everything including using xampp, wp-env, local, etc, but the problem persist. I can’t seem to see my custom blocks anywhere. I’m using wordpress 8.5.4 and php 8.2 (also tried 8.1 in local)

Any help would be appreciated.

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