How can i set model.scale as canvas size?

this is my code

 function (gltf) {
        model = gltf.scene;
        // model.scale.set(0.3, 0.3, 0.3);
        // model.scale.set(0.03, 0.03, 0.03);

        //모델 크기 계산
        const bbox = new window.THREE.Box3().setFromObject(model);
        const modelSize = new window.THREE.Vector3();
        bbox.getSize(modelSize);

        const scale = Math.max(
           GltfRef.current.clientWidth / modelSize.x,
          GltfRef.current.clientHeight / modelSize.y
        );
        // model.scale.set(scale, scale, scale);

        console.log(
          "Scaled Model Size:",
          scale
        );

i try to cal scale but…
its default scale(1,1,1) althought i didnt set the model scale
so, that scale size render too big model

thanks to read

You have a 3D camera, you need to position and scale your model relative to the camera viewport, or make the camera viewport fit the model, check the thread bellow: