Warning! If you don't want to know anything about Cyberpunk 2077, click away now. This article contains things that some may consider spoilers.
Night City is one of the busiest, most detailed game worlds on PC, which means it's easy to get overwhelmed. The map is sprinkled with hundreds of icons, your log is constantly being filled with new quests, and seemingly every ten minutes you're introduced to some new fixer or contact. So allow me to pick out some stuff you definitely don't want to miss, whether it's a cool quest, or a feature the game doesn't do a great job of explaining—or just doesn't explain at all. Night City will still feel overwhelming, but after reading this you might have a better idea of leads to pursue when you hit the streets.
Hunting down the rogue AI taxis
After the prologue you'll be reunited with your car. It'll be waiting for you in the parking garage of the megabuilding you live in. If you don't know where that is, there should be a quest in your log leading you to it. But the moment you start the engine, an automated taxi will ram into you. This begins a chain of quests for Delamain, a luxury fleet of driverless cabs. Hunting them all down might, at first glance, seem like busywork. They're spread all over the map, including out in the Badlands. But every one is interesting and fun, and finding them all unlocks one final quest where V is forced to make a tough decision. It might not seem like it at first, but this builds to become one of the best quests in the game.
Working with River Ward
At a certain point in the game you'll get a new contact: an NCPD detective called River Ward. As soon as his missions become available, take them on. This is some of the best side content in the game, with V getting tangled up in a seriously dark, twisted series of events involving a notorious Night City serial killer. River is an interesting character too, as are some of the shady NCPD types you meet as you work through his quests.
Using your ocular implant
The first cybernetic implant you get, as part of the main story, is a pair of new Kiroshi Optics eyes. Once you have them, and you don't have a weapon equipped, holding down the right mouse button (or the left trigger on a gamepad) will zoom the camera in slightly. But something the game doesn't tell you is that you can zoom in further, either by using your mouse's scroll wheel, or tapping up on your controller's directional pad. This is good for scoping out distant enemies, cameras, and turrets while in stealth, or just for admiring the incredible detail in Night City as you wander the streets.
Buying the Akira bike
Okay, it's not actually Kaneda's bike from Akira, but it's close enough. Throughout Cyberpunk 2077 you'll receive texts from fixers and other characters with vehicles for sale. At some point in the game you'll get a message from Wakaka Okado (leader of the Tyger Claws gang) offering a Yaiba Kusanagi CT-3X for 22,000 eddies. This is the bike pictured above, and once you get it, you won't want to drive anything else. The Kusanagi is parked in Westbrook, near the Skyline & Salinas fast travel point.
Talking to the cops in V's megabuilding
Once you've finished the prologue, you'll see a pair of NCPD officers banging on one of your neighbours' doors. They seem to be concerned about the person inside, a guy called Barry. This might seem like one of the many scripted moments you see as you explore the world in Cyberpunk 2077, but it's actually a trigger for an interesting quest. The guy in the apartment, Barry, is depressed about something, but the cops' lack of sensitivity means they can't get through to him. Which is where you, as a concerned neighbour, come in. This quest has a number of endings, including one that is pretty bleak.
Meeting up with Meredith Stout
Early in the game you'll be given the opportunity to work with Meredith Stout, a foul-tempered corpo representing the Militech megacorporation. If you do, later in the game you'll get a call from her inviting you to her hotel room. Mysterious. If you do you'll be rewarded with an iconic weapon, which is the highest tier of loot in the game. And this weapon in particular, a melee weapon, is, uh... unique. Just make sure there are no children in the room when you equip it.
Exploring the Konpeki Plaza hotel bar
Your first major mission in Cyberpunk 2077 takes place in Konpeki Plaza, a luxury hotel owned by the Arasaka corporation. When you arrive, disguised as a sharp-suited corporate arms dealer, you're given the opportunity to grab a drink in the bar before you start the heist. Definitely do, because not only do the overheard conversations of the bar's haughty patrons add some colour to the world, you'll also see a familiar face at the back of the room. If you don't speak Japanese, make sure you have subtitles enabled. Annoyingly, turning subtitles off also means you can't see other languages translated.
Visiting drop points
If you're anything like me, you'll be constantly shoving stuff in your pockets as you play Cyberpunk 2077. The world is absolutely heaving with loot, including an endless supply of junk items, common weapons, and other crap you don't really need. V has a carry limit, so eventually you're gonna run out of space and end up encumbered, which means you can't sprint. You can sell stuff at shops, but the easier solution is finding one of the many drop points scattered around the city. They appear as a cardboard box icon on your map and you can sell items to them, the same way you would to a vendor.