Write Iceberg table using Fabric Dataengineering

There are multiple ways to create a iceberg table, assuming destination as Onelake. 
1. Enable onelake setting to treat delta tables as Iceberg tables, this feature is in preview. You can enable this feature by going to workspace setting - > onelake setting -> Enable Delta Lake to Apache Iceberg table format virtualization (preview)

2. If you want to create iceberg table in snowflake and want to reside the data in onelake, you can follow the following article . 
Link : Getting Started with Iceberg in OneLake
Although, some permissions are not mentioned which are essential to create connection between snowflake and fabric. I have raised the issue on the link, you can check this link : Re: Snowflake iceberg table connection Issue - Microsoft Fabric Community

3. The first method, automatically converts exisiting and newly created tables in iceberg format, if you want to do same using code, you can follow the article. 
Link :Microsoft Fabric: Working with Apache Iceberg without shortcutting to the Iceberg Tables | by Christian Henrik Reich | Jul, 2025 | Medium