Unable to composer install

[neuronet77]

Problem 1

• Installation request for codeception/verify 0.5.0 -> satisfiable by codeception/verify[0.5.0].
• codeception/verify 0.5.0 requires php 5.6.* -> your PHP version (8.0.11) does not satisfy that requirement. Problem 2
• Installation request for doctrine/instantiator 1.0.5 -> satisfiable by doctrine/instantiator[1.0.5].
• doctrine/instantiator 1.0.5 requires php >=5.3,<8.0-DEV -> your PHP version (8.0.11) does not satisfy that requirement. Problem 3
• Installation request for fakerphp/faker v1.9.2 -> satisfiable by fakerphp/faker[v1.9.2].
• fakerphp/faker v1.9.2 requires php ^5.3.3 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 4
• Installation request for myclabs/deep-copy 1.7.0 -> satisfiable by myclabs/deep-copy[1.7.0].
• myclabs/deep-copy 1.7.0 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 5
• Installation request for phpdocumentor/reflection-docblock 3.3.2 -> satisfiable by phpdocumentor/reflection-docblock[3.3.2].
• phpdocumentor/reflection-docblock 3.3.2 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 6
• Installation request for phpdocumentor/type-resolver 0.4.0 -> satisfiable by phpdocumentor/type-resolver[0.4.0].
• phpdocumentor/type-resolver 0.4.0 requires php ^5.5 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 7
• Installation request for phpspec/prophecy v1.10.3 -> satisfiable by phpspec/prophecy[v1.10.3].
• phpspec/prophecy v1.10.3 requires php ^5.3|^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 8
• Installation request for phpunit/php-code-coverage 4.0.8 -> satisfiable by phpunit/php-code-coverage[4.0.8].
• phpunit/php-code-coverage 4.0.8 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 9
• Installation request for phpunit/php-timer 1.0.9 -> satisfiable by phpunit/php-timer[1.0.9].
• phpunit/php-timer 1.0.9 requires php ^5.3.3 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 10
• Installation request for phpunit/phpunit 5.7.27 -> satisfiable by phpunit/phpunit[5.7.27].
• phpunit/phpunit 5.7.27 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 11
• Installation request for phpunit/phpunit-mock-objects 3.4.4 -> satisfiable by phpunit/phpunit-mock-objects[3.4.4].
• phpunit/phpunit-mock-objects 3.4.4 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 12
• Installation request for sebastian/diff 1.4.3 -> satisfiable by sebastian/diff[1.4.3].
• sebastian/diff 1.4.3 requires php ^5.3.3 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 13
• Installation request for sebastian/environment 2.0.0 -> satisfiable by sebastian/environment[2.0.0].
• sebastian/environment 2.0.0 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement. Problem 14
• phpunit/php-code-coverage 4.0.8 requires php ^5.6 || ^7.0 -> your PHP version (8.0.11) does not satisfy that requirement.
• codeception/phpunit-wrapper 6.0.21 requires phpunit/php-code-coverage >=4.0.4 <6.0 -> satisfiable by phpunit/php-code-coverage[4.0.8].
• Installation request for codeception/phpunit-wrapper 6.0.21 -> satisfiable by codeception/phpunit-wrapper[6.0.21].

[alex-wdmg]

Not confirmed. You seem to be using PHP version 8, which is supported in Yii 2.0.45. (use version 2.0.40 / 2.0.42.1 as the most stable package for required PHP 5.6 or 7.*

In addition, please note that the errors are third-party software, not the wdmg/* vendor. Apparently their code is not yet ready to support the latest PHP version.

You can solve the problem by downgrading PHP CLI.

See more https://www.yiiframework.com/news/443/yii-2-0-45