Is it possible to create a proxy server application in java/android studio which will intercept the internet requests of devices on its a hotspot?

Question

I have been trying hard to figure this out by creating a ServerSocket, Listening for incoming cient response and using clientwriter/printwriter to write to the output stream of the client but the browser does not show the response(headers and body)... here is a snippet in my code

byte[] buffer = new byte[buffer_size];
            BufferedInputStream clientIstream = new BufferedInputStream(client.getInputStream());
            BufferedWriter clientWriter = new BufferedWriter(new OutputStreamWriter(client.getOutputStream()));
            clientIstream.read(buffer);

            String clientRequest = new String(buffer);

            Log.d(TAG, "request: "+clientRequest);

            String host = getHostFromRequest(clientRequest);
            Log.d(TAG, "the host is "+host);

            String hostSite=host.split(":")[0];

            //internet = new Socket(host, port);

            URL url=new URL("http://"+hostSite);
            //URL url2=new URL()
            connection=(HttpURLConnection) url.openConnection();
            connection.setRequestMethod("GET");

            int responseCode=connection.getResponseCode();
            String responseMessage=connection.getResponseMessage();
            Log.d(TAG, "code: "+responseCode+" response: "+responseMessage);
            // Send response status line to the client
            clientWriter.write("HTTP/1.1 " + responseCode + " " + responseMessage + "\r\n");
            clientWriter.flush();

            // Forward response headers to the client

            for (String header : connection.getHeaderFields().keySet()) {
                if (header != null) {
                    for (String value : connection.getHeaderFields().get(header)) {
                        clientWriter.write(header + ": " + value + "\r\n");
                        Log.d(TAG, "headers++ "+header+":"+value);
                    }
                }
            }

            clientWriter.write("\r\n");
            clientWriter.flush();

            // Forward the response body to the client
            InputStream inputStream = connection.getInputStream();
            OutputStream outputStream = client.getOutputStream();
            byte[] myBuffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = inputStream.read(myBuffer)) != -1) {
                // Check if the client is still connected
                if (client.isConnected()) {
                    outputStream.write(myBuffer, 0, bytesRead);
                } else {
                    // If the client is no longer connected, break out of the loop
                    break;
                }
            }
            outputStream.flush();

Browser displays nothing but rather says (url) did not send back a valid response