Welcome to TFK! Hopefully you'll find us to be a good resource and a helpful community. Glad you found us!
Cycling the tank is the most important thing for you to understand when first getting your feet wet in the aquarium hobby (or are returning to it after a long hiatus). Have a read over this sticky:
As for fish...well, that depends on a lot of factors. You've got a decently sized tank there so you do have a fair number of options but there are lots of things to consider. Let me throw this other article your way:
Essentially, how heavily you filter the tank depends on what fish you stock it with. A heavier stocking list requires more filtration (especially true on a non-planted tank) but fish are tolerant of various amounts of water movement (some fish really need calm water while others are river fish that like lots of water movement) so I think you should wait on the filter until you decide on the fish you want. Same for other things like decor and substrate.
As for the fish themselves, the most important thing to consider is your source water (usually your tap water). As the stocking article states, it's always easier to get fish based on your source water parameters than to mess with your water to suit the fish you want. Luckily, most (all?) liquid master test kits come with a pH test so you can test your tap water. You can usually find out how hard your water is by contacting your local water board but usually acidic water is soft while basic water is hard (but that's not always true).
Plants. Plants, plants, plants. Basically, plants have a ton of benefits in a freshwater aquarium. It's not difficult to set up a low-tech planted tank with some of the easier plants but it is something else to juggle when first getting into the hobby (or back into it, in your case). Check out Byron's stickies in the planted tank section of the forum for some great information:
If you don't want to tackle live plants just yet, you can always get silk plants. Though, there are some types of fish that don't really do well with plants and will even uproot artificial plants so that's something else to think about. How you decorate your tank is up to you, but personally I prefer the natural look with a natural looking substrate, driftwood, rocks and plants.