Compare a list from API and a list from my database (and create users)

Hello everyone and thank you in advance for your help, I have browsed the forum but I cannot find an answer to my problem.

I want to integrate an API into my app.
The goal is to create a new user in my app when a user is created in another app (example name: FLOWER)

With API Connector, I connected an API that allows me to list the user emails of the FLOWER app in my console. It works well.

Here is the workflow & script used:

Step 1: Call API FLOWER Get User

Step 2: Run JavaScript

let resultapi = Step 1 (FLOWER Get User)’raw body text; 

let JSONlength = Object.keys(resultapi).length;

for (let i = 0; i < JSONlength; i++){
    if (resultapi[i].adresse !== null && resultapi[i].adresse !== undefined) {
        console.log(resultapi[i].adresse.email);
    } else {
        console.log('No address for the user at index', i);
    }
}

When I run the workflow, all the email addresses of the FLOWER app users appear in my console.

Now I would like to compare this email list with the list of emails in my “User” table to identify the missing users in my Bubble app.

I have tested several scripts but it seems that
let myusers = Do a search for Users
blocks my entire comparison script.

How do I get the data from my table in JS format?

I anticipate another problem with a question:

Am I going about it the right way or am I going to find myself blocked to create new users in my app afterwards?

I am listening if you have already had this type of need with an API connection that you have managed to develop.

Thanks a lot !