Dell Latitude e6440 ssd options

Hello everyone... I want to know if I may upgrade my dell latitude with a NVMe SSD/ M.2 SSD and If so how.

I believe I should be able to upgrade using a SATA, just want to check if I have more options. I tried looking for the slots, could not find any.

If anyone know where the slots are if they exist, would highly appreciate if you could please share info.