Can you fit an aerator to any faucet?

A faucet don't need to match specific brand of aerator, other brands of aerator can also match them,  the design and the water shape can be determined by actual usage, so the design and water stream is univesal match 

But the point need to be concerned is the thread size,  both aerator and faucet spout all with thread,  thread divide into Female and Male,  if the faucet spout is in Female thread, the matching thread should be Male thread aerator,  the opposite is same.

Another point need to be considered is the flow rate, the smaller of the flow rate can save more water, like 1.2GPM, 1.5GPM,1.8GPM,2.2GPM and free flow rate in the market, you may buy according to the actual usage

If you want to DIY your faucet with more functions, can consider multi-functional faucet aerator,  not only with water saving, anti-splashing function, also can have more water chice by twisting the end part of the aerator