How to use Android Jetpack Paging 3 with PHP

I have succesfully implemented Android Pagination Library in my App, The problem is - I dont know the proper way to use it with my PHP code as BackEnd with regards to number of items to load etc.

get_feed.php

<?php

$limit = 2;

//find out how many rows are in the table
$sql = "SELECT count(*) FROM uploads"; 
$result = $conn->prepare($sql); 
$result->execute();
$total = $result->fetchColumn();

//total pages
$totalpages = ceil($total/$limit);

//get the current page or set a default
if (isset($_GET['page']) && is_numeric($_GET['page'])) {
// cast var as int
(int) $currentpage =  $_GET['page'];
} else {
//default page num
$currentpage = 1;
}


//if current page is less than first page...
if ($currentpage < 1) {
// set current page to first page
$currentpage = 1;
} 

//the offset of the list, based on current page 
$offset = ($currentpage - 1) * $limit;

$stmt = "SELECT * FROM uploads ORDER by id DESC LIMIT $offset, $limit";

//I get all requiresd data, send and encode in json
echo json_encode($obj);

?>
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All I want to do from this PHP code is to load 2 items at a time from the database.

Android codes

ApiService.kt

@GET(EndPoints.GET_RANDOM_FEED)
suspend fun getRandomFeed(
    @Query("page") page: Int
) : PostsResponse
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FeedSource.kt

class FeedSource(private val apiDataSource: ApiDataSource) : PagingSource<Int, Posts>() {

override suspend fun load(params: LoadParams<Int>): LoadResult<Int, Posts> {
    return try {
        //start from page 1 for undefined
        val nextPage = params.key ?: 1
        val response = apiDataSource.getRandomFeed(nextPage)
        LoadResult.Page(
            data = response.feeds,
            prevKey = if (nextPage == 1) null else nextPage - 1,
            nextKey =  nextPage.plus(1)
        )
    } catch (e: Exception){
        LoadResult.Error(e)
    }
 }
}
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FeedViewModel.kt

@Singleton
class FeedViewModel constructor(private val apiDataSource: ApiDataSource) : ViewModel() {

//I want to load 10 items at first
val feeds = Pager(PagingConfig(pageSize = 10)) {
    FeedSource(apiDataSource)
}.flow.cachedIn(viewModelScope)
}
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As it is, All items are loaded at once. I have set up the loadState Adapter which should only show a spinner when items are loading or error as the case may be. But right now, the spinner only shows when all item has been loaded and throws a HTTP 429 error

How do I make the app load 10 items initialy, then 2 at a time according to my PHP code?

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