Hi Fat,
Welcome to Microsoft Community.
I'm Hahn and I'm here to help you with your concern.
The Surface Laptop 7 with Snapdragon X Plus is designed to run on ARM-based processors, which are different from the x86 architecture used in traditional PCs. However, .NET Core 2.1 is compatible with ARM architecture starting from version 2.1.300. This means that you should be able to install and run .NET Core 2.1 on the Surface Laptop 7 with Snapdragon X Plus, provided that the device's operating system supports it.
For your work with .NET projects and SQL Server, it's important to note that while .NET Core 2.1 can run on ARM devices, you may need to ensure that any specific SQL Server features or libraries you rely on are also compatible with ARM architecture.
If you're considering pre-ordering the Surface Laptop 7 with Snapdragon X Plus for your work, I would recommend checking the compatibility of your existing projects and any dependencies they have with ARM architecture. Additionally, you might want to look into the possibility of using .NET Core 6 or later versions, as they offer improved performance and features that could benefit your projects.
I hope this helps. If there is anything not clear, please do not hesitate to let me know.
Your Sincerely
Hahn. W - MSFT | Microsoft Community Support Specialist