无法在主机上运行 Yii2 应用程序

Question

我有一个 Yii2 application，我想将它部署到 cpanel 中。因此，我在 servicess.co.uk 下创建了一个文件夹 public_html，然后将所有文件复制粘贴到该文件夹​​中。应用程序将使用路径 ../backend/web 运行。我的实时网址是 http://servicess.co.uk/backend/web/。当我运行它时，它给了我错误 Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 7.3.0".

Composer.json

{
"name": "yiisoft/yii2-app-advanced",
"description": "Yii 2 Advanced Project Template",
"keywords": ["yii2", "framework", "advanced", "project template"],
"homepage": "http://www.yiiframework.com/",
"type": "project",
"license": "BSD-3-Clause",
"support": {
    "issues": "https://github.com/yiisoft/yii2/issues?state=open",
    "forum": "http://www.yiiframework.com/forum/",
    "wiki": "http://www.yiiframework.com/wiki/",
    "irc": "irc://irc.freenode.net/yii",
    "source": "https://github.com/yiisoft/yii2"
},
"minimum-stability": "dev",
"require": {
    "php": ">=5.4.0",
    "yiisoft/yii2": "~2.0.13",
    "yiisoft/yii2-bootstrap": "~2.0.0",
    "yiisoft/yii2-swiftmailer": "~2.0.0",
    "luoxiaojun1992/yii2-tinker": "*",
    "kartik-v/yii2-grid": "@dev",
    "kartik-v/yii2-widget-select2": "@dev",
    "kartik-v/yii2-mpdf": "dev-master",
    "moonlandsoft/yii2-phpexcel": "*",
    "nirvana-msu/yii2-showloading": "1.0.*@dev",
    "kartik-v/yii2-krajee-base": "^2.0",
    "kartik-v/yii2-widget-spinner": "@dev",
    "edwinhaq/yii2-simple-loading": "*",
    "c006/yii2-submit-spinner": "*",
    "kartik-v/yii2-detail-view": "*",
    "fedemotta/yii2-cronjob": "*",
    "kartik-v/yii2-widget-datetimepicker": "*",
    "kartik-v/yii2-date-range": "dev-master",
    "phpoffice/phpspreadsheet": "^1.2",
    "linslin/yii2-curl": "*",
    "kartik-v/yii2-widget-fileinput": "@dev",
    "kartik-v/yii2-dialog": "*",
    "google/apiclient": "^2.0",
    "delight-im/str": "^2.4",
    "mongosoft/yii2-soap-client": "dev-master",
    "kartik-v/yii2-export": "@dev",
    "bower-asset/bootstrap": "^3.3",
    "npm-asset/jquery": "^2.2",
  "ext-json": "*",
  "ext-curl": "*",
    "convertio/convertio-php": "dev-master",
    "kartik-v/yii2-editable": "dev-master",
    "newerton/yii2-dynamicform": "*",
    "kartik-v/yii2-builder": "dev-master",
    "kartik-v/yii2-validators": "dev-master",
    "2amigos/yii2-multi-select-widget": "*"
},
"require-dev": {
    "yiisoft/yii2-debug": "~2.0.0",
    "yiisoft/yii2-gii": "~2.0.0",
    "yiisoft/yii2-faker": "~2.0.0",

    "codeception/base": "^2.2.3",
    "codeception/verify": "~0.3.1"
},

"config": {
    "process-timeout": 1800,
    "fxp-asset": {
        "enabled": false
    }
},
"extra": {
    "asset-installer-paths": {
        "npm-asset-library": "vendor/npm",
        "bower-asset-library": "vendor/bower"
    }
},
"scripts": {
    "post-install-cmd": "php init --env=Development --overwrite=n"
},
"autoload": {
    "psr-4": {
        "kartik\\spinner\\": "",
        "nirvana\\showloading\\": ""
    }
},
"repositories": [{
    "type": "composer",
    "url": "https://asset-packagist.org"
}]

}

.htaccess

Options -Indexes

# Rewrite engine
RewriteEngine On 

# condition with escaping special chars
RewriteCond $1 !^(index\.php|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php/$1 [L,QSA]

index.php

<?php
if (!empty($_SERVER['HTTPS']) && ('on' == $_SERVER['HTTPS'])) {
    $uri = 'https://';
} else {
    $uri = 'http://';
}
$uri .= $_SERVER['HTTP_HOST'];
header('Location: '.$uri.'/backend/dashboard/');
exit;
?>
Something is wrong with the installation :-(

目录结构

我被它困住了，不知道该怎么办。任何帮助将不胜感激