Hi I am trying to make spring java application which simply get simple cube mesh fbx and render by three.js. I have read offical three.js documentation and searched stackoverflow but got nothing

the below is part of html code for upload fbx filet

<form action="/isearch" data-transition="fade" enctype="multipart/form-data">
<input type="file" name="file" accept=".fbx" required/>
<buttontype="submit"></button>
</form>

and below is the part of controller code for /isearch mapping

@PostMapping("/isearch")
    public String uploadModel(Model model, @PageableDefault(size = 6) Pageable pageable,
                              @RequestParam("file") MultipartFile file, HttpServletRequest request) {
        if (file.isEmpty()) {
            logger.warn("Upload attempt with empty file");
            return "redirect:/uploadError";
        }

        String directoryPath = "src/main/resources/static/3dmodels/";
        String originalFileName = file.getOriginalFilename();
        Path path = Paths.get(directoryPath + File.separator + originalFileName);

        try (InputStream inputStream = file.getInputStream(); Reader reader = new InputStreamReader(inputStream)) {
            if (!Files.exists(path)) {
                Files.copy(inputStream, path);
            }

            String baseUrl = ServletUriComponentsBuilder.fromRequestUri(request)
                .replacePath(null)
                .build()
                .toUriString();

            String fileUrl = baseUrl + "/3dmodels/" + originalFileName;
            model.addAttribute("fileUrl", fileUrl);

            logger.info("File successfully uploaded and accessible at: {}", fileUrl);

        } catch (IOException e) {
            e.printStackTrace();
            logger.error("Error occurred while uploading file", e);
            return "redirect:/uploadError";
        }
        return "isearch.jsp";
    }

and the below is the html file code with js code for rendering cube

<div id="canvas" background-color: transparent;">

            </div>
            
<script>
    var modelPath = "${fileUrl}";
    type="module" src="${pageContext.request.contextPath}/resources/js/3drender.js">
</script>           

    import * as THREE from 'https://unpkg.com/three/build/three.module.js';
    import { FBXLoader } from 'https://unpkg.com/three/examples/jsm/loaders/FBXLoader.js';

    let scene, camera, renderer, clock, mixer;

    function init() {
        const container = document.getElementById('model-container');

        scene = new THREE.Scene();

        camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
        camera.position.set(0, 100, 200);
        camera.lookAt(scene.position);

        renderer = new THREE.WebGLRenderer({ alpha: true });
        renderer.setClearColor(0x000000, 0);
        renderer.setSize(container.clientWidth, container.clientHeight);
        container.appendChild(renderer.domElement);

        const ambientLight = new THREE.AmbientLight(0x404040, 2);
        scene.add(ambientLight);
        const directionalLight = new THREE.DirectionalLight(0xffffff, 3);
        directionalLight.position.set(0, 10, 10);
        scene.add(directionalLight);

        const loader = new THREE.FBXLoader();
        loader.load('${imagePath}', function (object) {
            mixer = new THREE.AnimationMixer(object);
            const action = mixer.clipAction(object.animations[0]);
            action.play();

            object.traverse(function (child) {
                if (child.isMesh) {
                    child.material = new THREE.MeshStandardMaterial({color: 0xff0000});
                    child.castShadow = true;
                    child.receiveShadow = true;
                }
            });
            object.scale.set(0.1, 0.1, 0.1);
            scene.add(object);
            animate();
        });

        function animate() {
            requestAnimationFrame(animate);
            const delta = clock.getDelta();
            if (mixer) mixer.update(delta);
            renderer.render(scene, camera);
        }

        clock = new THREE.Clock();
    }

    window.onload = init;

it shows html rendering page but I cannot see nothing

I want to render simple cube mesh in website by uploading simplecube.fbx

but there are few materials for references

If there exist any tutorial for this please give me a hint please

thank you