PHP implementation based on Codeigniter 2 framework

The site management system is written in PHP based on the Codeigniter 2 framework. The store uses a modular architecture (HMVC), all code is broken down into modules and is located in the application / modules folder.

We need to implement comments on SEO audit

To begin, estimate the time and cost of implementing these items (detailed description in the file)

1.1 The main mirror of the site is determined and 301 redirects are implemented from the non-main mirror of the site to the main one.
1.5 Canonical URLs are defined and the canonical tag is implemented.
1.9 Search-ineffective pages are closed from indexing.
1.6 Pagination pages have been optimized.
1.6.4 Next and prev tags have been introduced.
1.6.1 Redirect to the main page of pagination is configured.
1.6.3 All pagination pages are available.
1.6.2 The SEO text is located only on the promoted page.
1.13 An XML sitemap has been created, a link to it is placed in the robots.txt file.
1.15 GET queries are correctly generated when marking URLs.
1.18 If the page is not available, a redirection is made.
2.1 The meta information of the page (Title, Description, Keywords, H1) is implemented. Based on the examples and templates developed during the audit.
3.7 A call analytics system is connected to track the main traffic sources.