How can I use LottieFiles to render animations?
Sure it is. See the LottiFiles sample. First, you need to add the  Lotti player library yourself first.

https://unpkg.com/@lottiefiles/lottie-player@latest/dist/lottie-player.js


Learn about adding Adding stylesheets (CSS) and JavaScript (JS) to a Drupal theme in the docs.

And second, find a way to place the Lotti markup on the page somewhere.

&lt;lottie-player 
    src="https://assets4.lottiefiles.com/packages/lf20_32NcN8.json" 
    background="transparent"
    speed="1"
    style="width: 300px; height: 300px;"
    loop controls autoplay&gt;
&lt;/lottie-player&gt;


I'd probably have a field for that where you only paste the animation file URL or upload the animation file which then gets wrapped by the corresponding markup via a custom field formatter.

&lt;lottie-player 
    src="{{ field_lotti.entity.url }}" 
    background="transparent"
    speed="1"
    style="width: 300px; height: 300px;"
    loop controls autoplay&gt;
&lt;/lottie-player&gt;