composer install has shown error

I cloned Akaunting from Github into my pc, when I run
composer install
it shows errors saying like I have installed PHP 8 and required is 7.3.0.
Your lock file does not contain a compatible set of packages. Please run composer update.

Problem 1
- Root composer.json requires php ^7.3.0 but your php version (8.0.0) does not satisfy that requirement.
Problem 2
- dingo/api is locked to version v3.0.5 and an update of this package was not requested.
- dingo/api v3.0.5 requires php ^7.2.5 -> your php version (8.0.0) does not satisfy that requirement.
Problem 3
- dingo/blueprint is locked to version v0.4.2 and an update of this package was not requested.
- dingo/blueprint v0.4.2 requires php ^7.2.5 -> your php version (8.0.0) does not satisfy that requirement.
Problem 4
- doctrine/dbal is locked to version 2.11.3 and an update of this package was not requested.
- doctrine/dbal 2.11.3 requires php ^7.3 -> your php version (8.0.0) does not satisfy that requirement.
Problem 5
- league/omnipay is locked to version v3.1.0 and an update of this package was not requested.
- league/omnipay v3.1.0 requires php ^7.2 -> your php version (8.0.0) does not satisfy that requirement.
Problem 6
- monooso/unobserve is locked to version v3.0.0 and an update of this package was not requested.
- monooso/unobserve v3.0.0 requires php ^7.3 -> your php version (8.0.0) does not satisfy that requirement.
Problem 7
- omnipay/common is locked to version v3.0.5 and an update of this package was not requested.
- omnipay/common v3.0.5 requires php ^5.6|^7 -> your php version (8.0.0) does not satisfy that requirement.
Problem 8
- phpoffice/phpspreadsheet is locked to version 1.16.0 and an update of this package was not requested.
- phpoffice/phpspreadsheet 1.16.0 requires ext-gd * -> it is missing from your system. Install or enable PHP's gd extension.
Problem 9
- doctrine/dbal 2.11.3 requires php ^7.3 -> your php version (8.0.0) does not satisfy that requirement.
- barryvdh/laravel-ide-helper v2.8.2 requires doctrine/dbal ~2.3 -> satisfiable by doctrine/dbal[2.11.3].
- barryvdh/laravel-ide-helper is locked to version v2.8.2 and an update of this package was not requested.

Hello Abdul,

You are using php 8.0. However the dependencies are expecting php 7.3
You may downgrade to php 7.3 or 7.4 or run "composer update" instead. However, not sure that composer update will make the thing..Some dependencies may not be ready yet to php 8.

Anyway. That's it.

Thanks, it worked. I was thinking it should support the latest PHP versions as well. Maybe the problem is PHP major version change.

Glad it helps!