XPS 8940, replacing and upgrading NVMe SSD?

Hello.  I am looking to upgrade/replace my current NVME SSD 2TB M.2 PCIe for something much higher due to many huge games, and have the following questions:

1. What is the max TB I can get for my specific system?

2. Aside from it needing to be an SSD drive, is there any other type of info I will need to do so (Connectivity? Data Transfer Rate?

3. Anything else I'd need to know/look for?

Thanks in advance.