I can see how unit control could seem a little wonky at first glance; unlike Civ4 and 5 where you can move units with a simple right click in Alpha Centauri the most common way to move units is to left click on the unit then drag the mouse to where you want the unit to move (a green line will appear indicating the path the unit will take). There's also much less of a GUI for controlling unit actions. If you right-click on a unit a menu of unit actions will come up that you can choose from, but there are also hot-keys for all unit actions and it's recommended to learn at least the common ones as it makes playing the game a lot easier and faster.
For city management, there are three resources you need to worry about, just like the other Civ games- minerals (production), nutrients (food), and energy (money). Just like the other Civ games you can improve the areas around your cities (terraforming) to improve resource output, although there are quite a few additional improvement options than the other Civ games have (and you can have multiple types of improvements per tile if the terrain allows for it and the improvements are compatible). Something a little bit different from the later Civ games is the unit upkeep is managed on a per-city basis; units a city is supporting is shown in the lower right of the city screen. You'll want to keep an eye on this, as early in the game having one city crank out a bunch of units can quickly kill that city's production. For managing your citizens there are three types of citizens- regular citizens, talents, and drones (and any citizens that aren't working tiles can be various types of specialists). Drones are unhappy citizens, while talents can basically be viewed as extra-happy citizens. If the number of drones in a city becomes greater than the number of talents then drone riots will occur and the city will basically shut down until you end the drone riots (most easily done by re-assigning some citizens to be specialists). There are various city buildings that increase the number of specialists and decrease the number of drones that you'll be able to build.
For civilization management you have research, diplomacy, and overall civilization income like the other Civ games. Research can be a little bit different as you're not shown an overall tech tree, but rather just given the option to choose between research goals from time to time (there's also a setting at the beginning of each game that can make it so you can only choose general research direction rather than specific goals). There's also social engineering which is basically like the civics in the Civ games. Something rather different from the Civ games is the workshop, which allows you to design your own units based on available technology. The game will automatically design plenty of units as you discover technology, but you can also create customized units if you feel so inclined.
There's plenty more to the game, but that should at least give you enough of the basics to get started. Most of the options in the game are hidden in menus, so I'd recommend poking around when you first start to get a feel for what all is available and where it's all located.