As a newbie myself, now that I am three months in, I wish I had done things differently. This site is about self pool maintenance. However, learning how to run a pool takes time and experience. It's much more difficult to get the water balanced for a newbie than the seasoned veterans on here who have had their water balanced for years. Most likely, you are inheriting a pool which has been neglected. If I were to start over, I would have used the chlorine pucks in the beginning (which are shunned on this site), because they are somewhat self regulating, something you need while trying to learn how to run a pool. Because I didn't know what I was doing, I have pool stains and three trips to the doctor to show for it. I've got a mess on my hands. None of us wants to harm our pool or ourselves, but diving in with both feet, so to speak, is not the answer.
Here is what I would do in order.
1) Use chlorine pucks to start.
2) Get a full test kit, and learn how to use it based on the directions. Don't bother taking your water to the pool store. They do not do accurate work, and can get you going in completely the wrong direction.
3) Determine if your water needs changing due to high cyanuric acid or high calcium hardness. There is no use in trying to balance bad water. Don't even attempt it.
4) Get all the chemicals you will need to keep your water balanced for the time you later remove the pucks, and learn how to use the chemicals prior to removing the pucks. This generally includes bleach and muriatic acid. Example: You don't just want to pour acid into a pool, because that can harm the finish. There are techniques, which I wish this site had outlined someplace, to prevent pool and people damage.
5) Compute how much water your pool holds using the Pool Calculator (at the bottom of the page at The Pool Calculator).
6) Use the Pool Calculator to get a feel for how much of each chemical will change the chemistry, e.g. a quart, a gallon, etc. will change how many parts per million?
7) Make sure all your pool equipment is in good shape. That includes pumps, filters, and pool sweeps. I would even recommend you clean the filter, know how to clean the skimmer basket, and pump basket. Get everything fixed first. Have a pool brush, net, and perhaps a vacuum.
8) Now it's time for the last water test, and then take the pucks out. Now it will be much easier. Your water is good. You know how to use the chemicals.
I hope this helps another newbie avoid my mistakes.