It looks like the website you linked is using a combination of a database and a search engine to provide the results. The website likely has a database of vehicles and their associated parts. When you enter your vehicle information, the website searches the database for the associated parts and displays them.
It is possible that the website is using an API to access the database, but it is also possible that the website is using a custom search engine. To determine for sure, you would need to look at the code for the website.
If you are looking to create a similar website, you could use a combination of a database and a search engine. For example, you could use a MySQL database to store the vehicle information and a search engine such as Elasticsearch to search the database. You could then use an API to access the database and search engine.
// Example code for accessing the database and search engine
// Connect to the database
$db = new mysqli('localhost', 'username', 'password', 'database');
// Connect to the search engine
$es = new Elasticsearch\Client();
// Search the database
$query = "SELECT * FROM vehicles WHERE make = 'Honda'";
$result = $db->query($query);
// Search the search engine
$params = [
'index' => 'vehicles',
'body' => [
'query' => [
'match' => [
'make' => 'Honda'
]
]
]
];
$result = $es->search($params);