On this page of the Deathloop game guide, you will learn whether you can use area maps and the world map. This information may be critical if you intend to explore 100% of each district in Blackreef.
At first glance, Blackreef island appears to be a very extensive location, but unfortunately you don't have the option to freely explore the game world. There are only 5 Blackreef districts available and you are limited as to which sections you can explore.
The world map isn't available in this game. You can find maps of the entire island as you progress through the game, but they have no practical use. You can only select which location you want to visit from the tunnels section (as well as the time of day). The world map is therefore unnecessary in these circumstances.
Unfortunately, you can use the area map by default during gameplay - whether it's a full-screen map or a mini-map. An exception to this rule are large district maps found in the game world (pictured in the screenshot). Interacting with them lets you add them to your character's journal as discoveries, allowing you to select and view them in the discovery list to zoom into them.
Unfortunately, the maps you find aren't interactive - they don't display your character's current location and there is no cursor on the screen. They can only provide a bit of additional support - the red objects on the maps indicate buildings which you can visit.
Fortunately, Blackreef's districts are not very extensive. Additionally, by repeatedly visiting the same districts, you will be able to memorise them better and remember their most important locations and transitions.