Finalize the site in php

It is necessary to finalize the site on the platform of the doc part. We would like to add features to it. I already have the TOR, I attached it.
The editing code is open. I will provide access to hosting.
Our website: https://autozapad54.ru/ Platform: https://docpart.ru/
Price by agreement


The meaning of the task is that after specifying the car in the garage, the site, roughly speaking, gets on the same rails and shows only what suits the specified car. At the same time, the user has the opportunity to select products by category from the main page of the site. That is, after linking to the user of the car, going, for example, to the shock absorbers section, exactly those shock absorbers that are suitable for this particular car will be shown.
Now, the user must first enter his car in a special form and only through the scheme of the car, choosing the original number, can he choose a spare part for himself. In this case, the options are provided by a list of

Setting up search capabilities for certain filters

After filling out the form in the garage, the car is saved in the cache.