Just trying out Spline with React, the implementation was very simple and straigthfoward.
The project was built with "npx create-react-app splinefun" and installing React Spline like so "npm install @splinetool/react-spline"
All I had to do to add the component in App.js was to copy and paste the Spline component in the App div like this
function App() {
return (
<div className="App">
<header className="App-header">
<Spline scene="https://prod.spline.design/78Ldjfp770bmw7rD/scene.splinecode" /> {/* Add Spline component */}
</header>
</div>
);
}