Prokayrotic and eukaryotic cells are alike because both of them have DNA. Both cell types also are capable of responding to their environment. Both cell types are capable of reproduction. Both cells can grow and develop. Both cells obtain and use energy. Both cell types have an outer cell membrane that contains the cytoplasm.
Beyond the above characteristics though, there are few other similarities. A prokaryotic cell is quite primitive. It houses a cytoplasm and some free floating DNA inside of its cell membrane. On the other hand, a eukaryotic cell is much more complex. It contains many internal cell organelles. It has things like a mitochondria, a golgi complex, an endoplasmic reticulum, and many other structures. The biggest difference between the two cell types is that a eukaryotic cell has a nucleus. Prokaryotic cells do not have that.
The way that each cell reproduces is different too. A prokaryotic cell reproduces through binary fission. Eukaryotic cells reproduce through mitosis.