Complete internal optimization of the site

Developing the structure of the site ideal for promotion in search engines even before the site is created.
Internal Optimization:
Complete technical audit of the site.
Implementation of the necessary changes on the site.
Composition of the semantic core of the site
Removing duplicates of pages.
The CPU.
Writing unique texts on categories and product cards
Optimization of tags and meta-categories.
Site map of Sitemap.xml.
The Robots.txt file.
the translining.
404 pages.