Sorting, Filtering, Data Search. How does it all work?

Question

Programming

Greetings to all. I would like to get an understanding for myself about ,search and filtering (to tell the truth, I don’t even know how to call it correctly).
I will describe the essence of the issue.
Let's say there is a product in the online store that I need to find, I go and select the country, city, approximate price, product classification, drive in its name and it shows me 5 suitable results according to the criteria that I chose.
Or an example, like on a dating site, social networks, I need to find certain suitable girls, I go and click on the country, city, age, etc., and as a result it shows me 100 suitable girls. Or let's complicate the task altogether. I have my profile says that I'm from Russia, Moscow, I'm 25, blond, blue eyes
I choose the criteria for finding a girl, and how these criteria adapt to mine in the profile. And at the end I will get the result of not 100 girls, but 5 who were looking for a guy from Moscow, 22-27 years old, blond or brunette, blue eyes.
So I described what I mean (Tell me how it's called correctly :) )
I've been in the IT world for about a month, I'm studying HTML CSS, for now I'm trying to typeset, and touch PHP, MySQL a little.
There is a project in my head that I plan to implement on my own. And in this project there will have to be, so to speak, "FILTERS" with their different interpretations.
I so suspect that it all works on PHP.
I would like to get at least a cloudless understanding of how these "FILTERS" work, what they are written on, and any other thoughts on this issue, if it's not difficult for you. So, give at least some kind of understanding. It's very interesting to me
Thank you for your attention.

Answer 1

I so suspect that it all works on PHP.

And not only. There are many backend languages. But in general, yes, everything works on the server side.
They touch girls and learn languages ​​:)
If we take specifically a bunch of PHP / MySQL - then most often there is a banal selection of the fields of the table. As soon as you get to work with the database, you will understand what I mean. There is nothing supernatural in this matter.
I'd better make you a plan for further study:
The time for this list will take from 4 to 12 weeks.

Answer 2

"I suspect that it all works in PHP"
No. The means of their construction will work on PHP, the processing of the filter itself is the task of the DBMS. Your own mysql, for example.
"I would like to get at least a cloudless understanding of how these "FILTERS" work, what they are written on, and any other thoughts on this issue, if it's not difficult for you. So to say, give at least some kind of understanding. It's very interesting to me "
. start with SQL. Maybe later - ORM,