Combining your functionality with the functionality of Wordpress?

Question

CMS

Hello!
I am studying web development. Already learned PHP and moved on to choosing admin panels for further projects. As a result, I chose wordpress, as the most popular of all that currently exist.
But while researching, I had a question. I'll start a little further. Suppose I need to create a website where there will be registration, a product catalog with flexible filtering, the ability to leave feedback on the site (the data will be saved in the database I created and then displayed on a separate page) and a feedback form. So, I can implement such a site in PHP and it will fully work for me. However, when integrating such a site on Wordpress, all my PHP code will stop working. In order to restore the functionality, I will have to install plugins that will replace a specific function on the site. However, such plugins either don't meet my needs or don't work properly. The question follows from this. Is it possible to use wordpress exclusively as a shell, so that the client himself can then add his own texts and products,
To make it a little clearer the essence of the issue, I will give an example with the same filtering. I want the client, through the admin panel, to only be able to add a new product to the database in a form convenient for him, and having already written my PHP code, I will simply output these products via sql queries on a specific page. And when using filters, add the appropriate filter to the sql query.
Please tell me, is it possible to use what I described above using the wordpress shell? And if not, then tell me, are there other shells that fit my problem?

Answer 1

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