GPM doesn't work

I tried everything but I'm not able to make GPM work!
I installed MAMP and a Grav skeleton on my macOS (Catalina 10.15.6).
When I try to use the gpm on my Terminal (i.e. $ bin/gpm index), I receive the following error:

dyld: Library not loaded: /usr/local/opt/curl-openssl/lib/libcurl.4.dylib
Referenced from: /usr/local/bin/php
Reason: Incompatible library version: php requires version 11.0.0 or later, but libcurl.4.dylib provides version 10.0.0
Abort trap: 6

I tried everything but nothing works... Please help me!
Thank you very much

When you say you've tried everything, what exactly have you tried? Your system is reporting an outdated version of Curl, which PHP is using. I'm not familiar with how software is updated on macOS, but I imagine there is a homebrew-command that will upgrade Curl.