I need some help about my Shopify first app test

[devapp972]

Hello,

Problems: Unable to test my very first Shopify app.

-I installed ngrok,node.js and Shopify CLI 3.0;
-I did the commands like npm run dev and similar commands;
-I created an application store (dev) as recommended.

But the following error is displayed on the Shopify site, in the part of the application that must be tested:

"You are about to visit:
<ngrok site>
Website IP: <IP address>

This website is served for free through, etc..."

With the "Visit Site" button

, and when I click again on "Visit site", it reaffirms this error.

What to do?

Thank you for your help.