As Slinky mentioned, first steps first. Test kit, you need a
TF-100 or a
Taylor K-2006 (either one will do, the TF-100 is the recommended kit by this forum). This is the most important thing right now. With this you can accurately test your pool levels and the forum can help you turn that pool into the sparkling puddle of joy it was intended to be.
While you are waiting, do what Slinky said and start getting the bottom cleaned up of debris and muck as much as possible. Sediment is your enemy in the
SLAM process, which is what you'll need to do. Powdered shock and algecide aren't really used around here. All you'll need for certain is a source of liquid chlorine (bleach is viable). You may possibly need CYA but wait on the test kit results before worrying about acquiring that.
Go read everything you possibly can in
Pool School and learn the philosophy of this forum and what it takes to have a "trouble free pool". It works, truly. My personal pool thread (linked in signature) is a testament to the process. Go read through other threads in this forum and you'll see the same in countless instances. Do the reading, share your results, and let us help you through the process. Be sure to read up on the SLAM process.
