Select list by category

Hi, thanks for your patience

I have two questions to solve the same problem

Stage
I have a database of places with 3 or 4 different categories
I have buttons, on a page, for each category.
When the user presses a button, I would like to display a page with only the category selected by the button.
But I do not will like to add a category selection component on the page.

My two questions are:
Is it possible to filter the results by category and show only the selected results without filtering the search by the user (just press the button and not on the results page)?
Or another option
Is it possible to use different databases and select the database used with the button?

I wait your answer

Thank you