Getting local advice is important here. You could spend a few years learning general gardening "theory" and then apply it to your particular situation, but that probably isn't the best way to get started!
Take note of which of your neighbours seem to have "good" gardens, and talk to them. Most keen gardeners are happy to give advice, lend tools, or even donate you some plants.
One universally applicable piece of advice: don't rush to do any major work until you have lived there for a year and taken note of everything you already have. For example you might have a lot of spring flowering bulbs which are currently invisible underground. If you discover them by digging them up by accident, you can usually identify the general species, but it is impossible to tell exactly which varieties or what the flower colors are except by "seeing what comes up" next spring. For example tulip bulbs all look pretty much the same, but the flowers might be any color of the spectrum from white to black, and the plants might grow anything from 6 inches to 3 feet tall.
If you want some "instant gratification" because the garden currently doesn't look interesting, go for annual plants in the first year. After midsummer may be too late to sow seed (depending on your climate, and how soon winter sets in) but you can buy plants either from garden centers or supermarkets. Since they will only live for one season whatever happens, any mistakes or bad choices won't turn into long term problems
As for pruning shrubs and trees, don't forget that plants in the wild get along just fine without people messing about with them every year. You won't kill or damage any established plants by leaving them alone for a year or two, and doing the wrong thing can wipe out the following year's flowers completely if you try to "reduce the size of the plant" but cut off all the new growth that would flower next year, for example. (A good general rule: prune flowering shrubs and trees immediately after flowering, not at a different time of the year).
The most important piece of advice is "have fun." and remember that all gardeners learn by making mistakes all the time. It's just after the first 20 or 30 years, the type of mistakes you make tend to become less obvious :)