Here is a link to the components for the FC test you should use instead of the drop one. The drop one is more for "Is there any FC in my pool?" kind of testing. The powder test is much better. FAS/DPD Chlorine & CC's test
Here is a link to videos to help you do it:
Once you get the water clear with the drops stop the test then. It can turn back to pick if you let it sit for a little while but don't worry about that. Once the water goes clear you are done with that test.
I use liquid chlorine I get from the local pool store or Ace Hardware up the road from me. You need to add some each day or you will end up with algae. Here is a link to show you a basic pool care schedule: