Sorry for the short comment currently playing a game with no pause function
The Controls are explained in Help option on Menu and you can almost 'pause' with M key while looking at the map you might find. (Game time slows down, while you look at map, but not quite paused). This encourages you to keep playing :-)
The basic controls are WASD keys to walk. Hold down left Shift and W to run forward for example but watch your Stamina bar and body temperature. Use space bar to jump/climb. Use Esc key to hide/show the mouse cursor. (It also locks the cursor to center which is helpful for players with two monitors.) Use mouse to look around. 'C' to toggle compass on/off.