No images in local folder

I'm doing a page with Flask, HTML, I have made some templates that I did with materialize, in some sections I have images that are in the background, for example, when I add it in the flask project, it is no longer visible. for example I have this

<section class="slider">
        <ul class="slides">
          <li>
            <img src="images/compartir2.jpeg" class="responsive-img">
            <div class="caption center-align">
              <h2>Comparte tus contenidos!</h2>

but the image can not be seen, I would appreciate your help!