Using Composer Command

I think you are trying to require musonza/chat in the clone of that package or your project name has the same name as the package that you want to install/require.

You should install musonza/chat on the laravel project because it's a package for laravel.

Try step below to create a laravel project :

composer create-project --prefer-dist laravel/laravel chat

go to chat folder then install the package:

composer require musonza/chat

then publish the assets of that package:

php artisan vendor:publish

See musonza_chat.php for configuration

then run the migrations:

php artisan migrate

Note: The requirement of laravel 6 is PHP 7.2 or above, so please install it