for 3050 MT it has a 2.5 bay for two 2.5" ssd.  cables should be included already.

for 3050 SFF you can use a Dell 2.5 to 3.5 adapter which can hold two ssd.  install the adapter in the 3.5 hdd bay.

SATA power cable will likely have 2 power plugs.  May need another SATA data cable though unless there's 2 already in the machine for HDD's/SSD's.