Even if you buy a memory module with the same model number as your current one they're still not guaranteed to work together.
The recommended way is to buy a kit consisting of 2x8gb modules. The ones sold in kits are actually tested working together.
The difference between those 2 modules as far as I can see is:
CT102464BA160B is DDR3 running at 1.5V.
CT102464BD160B is DDR3L running at 1.35V.
Both will run by default at the same voltage(1.5V most likely) when put together so that's not the issue.
Mixing and matching RAM is a gamble so I won't recommend it... you can give it a try if you can return the new module though.
If they'll work together you'll probably still get dual channel to work.
Dual channel means that both memory modules can be accessed simultaneously, doubling the memory bandwidth. You'll need to look on your motherboard manual to check what configurations will run in dual channel. If you have 2 memory slots, obviously the memory should be put in slots 1 and 2. If you have 4 slots, you'll most likely have to put them in slots 2 and 4(or A2 and B2... they're numbered from thr CPU socket) so they'll run in dual channel(double the speed compared to single channel).