Hello @Omar Cruz,
welcome to this moderated Azure community forum.
Yes, the AZ-220 Azure IoT Developer certificate is not available anymore.
There are still several IoT related free MS Learn modules available so you can still work yourself to the training program.
Here is a curated collection based on the original AZ-220 program.
Azure IoT and related training helps you to sending data from devices (owned by an OT engineer) to streams and databases (owned by a Cloud data engineer).
So you can either entend your knowledge and certification to the OT side or the Cloud data side).
I expect you are interested in the cloud side...
At least, you need to take the AZ-900 Azure Fundamentals exam.
From there, the Azure Data Engineer DP-203 exam is a good choice.
It's also recommended to look at the Azure AI Fundamentals because IoT is more and more combined with AI eg. vision on the edge or for decision making in the cloud.
If the response helped, do "Accept Answer". If it doesn't work, please let us know the progress. All community members with similar issues will benefit by doing so. Your contribution is highly appreciated.