ReFlex, it's "Fleck", not Treck, and it's generally considered to be a fine valve. I've got the non-metered version of your valve, which I think is a Fleck 2510EC. If I'm right, a service and startup manual can be found on line by Googling "The Fleck 2510 Econominder Metered On Demand Water Softener" and checking out the first few hits. Read that over to get familiar with the unit and terminology, then come back with your specifics (water test results and expected demand, based on number of fixtures, family size, etc.), and the experts here might give you some help. Setting the unit up properly is a fairly simple step-by-step process. The hard stuff is some internal settings in the valve, which we can probably assume were set during the original installation by somebody who knew what he was doing. All that's left is the easy stuff -- setting the time of day, and the number of gallons of water to treat before regenerating. To set the latter correctly, we need to know your specific numbers.
While you're waiting for advice, you could start by just emptying and cleaning the brine tank (the big tank with the undissolved salt in the bottom), and going out to the nearest Sam's or Costco and picking up a few bags of salt -- I usually buy 8 at a time. The odds are high that everything else is OK. Worst case, you might have to replace the media, but I doubt that will be the case, and there are hundreds of YouTube videos showing you how to do that.
Update: See the lttle instruction plate on the front that tells you how to regnerate? Follow those instructions. Maybe read the manual first... I think the advice to wait 3 hours is to give the salt time to dissolve. So the sequence would be: clean brine tank (if necessary -- your call), add some salt (say 3 bags to get started), add 5 gallons of water for startup, wait 3 hours, plug it in, then turn the knob as directed.
Another update: Google {Penn State F-141 "Water Softening" } for a brief guide to what water softening is al about. Also, as they point out, you can call your local utility to get your current water test values. A local test is better, but their data is government-mandated, and so is good enough for government work.