Understanding PCIE lanes for storage

[sniperone]

Just finished putting together my new computer with a 12700k and z690 motherboard and rtx 3070 and have gone full nvme with 2x 1tb and 2 x 2tb drives populating all sockets
Now my old build i was running with a 2 x 4tb hdd and looking forward on the new build and rather than swap out drives for larger ones im alittle baffled when it comes to PCIE lanes and storage
my understanding is 20 lanes for cpu taken by gpu and one nvme . Not sure what im left with for future upgrade ,also looking to install a dual thunderbolt card so that will take up lanes also .
Just thinking forward as i do heavey video and photo work plus games and storage fills quickly and rather than swap out drives was looking at a controler card to add more nvme storage but not sure how it all works

 

[sniperone]

All the nmve drives are samsung 980 pro 4.0. So it looks like i have used all 12 PCIe lanes on the chipset and only have the 16xPCIe 3.0 lanes left .

 

[sniperone]

Thanks guys have emailed gigabyte customer service and they tell me the thunderbolt card will use 4 pcie 3 lanes so that leaves me 12 pcie 3 lanes for storage so could in theory add another 3 gen 3 nvme drives should i need them .