Furutaka was the lead ship of a class of two interwar-era heavy cruisers of the IJN. She had the distinction of being considered the first modern heavy cruiser in the IJN service, and paved the way for more advanced designs, such as the closely related Aoba-class. She was sunk in 1942. Historically, Furutaka was armed with a battery of six 201mm guns in single gun turrets, which were later rearranged into three twin gun turrets, and four secondary guns. She also carried six twin torpedo launchers, later changed to two quad launchers, and a catapult for a reconnaissance seaplane, although these are not featured in game.
With Furutaka you have left the WWI-era armored cruisers and entered the world of modern CAs. Although Furutaka can be a frustrating ship to get through, it will get you acquainted with the core mechanics of the rest of the IJN CA line, and well worth the trouble once you move on to the Tone. Now, compared to the short and stubby Izumo, Furutaka's long, narrow form is quite different to handle, and requires much more attention paid to gun convergence especially when targeting smaller ships. Even bigger culture shock is the sudden absence of a massive secondary battery - now you are restricted to only two secondary guns per side. From here on, working your accurate main guns to their full potential will determine your success. Although you are a bigger target, Furutaka has much better speed and maneuverability than Izumo, opening your options from simply slowboating alongside battleships. You are now much more able to move around the front to put your firepower where it is needed, perform flanking attacks, and harass distracted capital ships. Your secondary guns are not numerous, but are now able to fire AA rounds, and shooting down enemy scouts is one of your newfound abilities that will greatly benefit the fleet. But don't overlook the secondaries for surface work - they can often make the difference in a tight duel, or sink a fleeing ship while your main guns are reloading. The biggest limitation of Furutaka is the lack of a scout, which makes you dependent on recon provided by your teammates, and restricts more ambitious flanking moves.
Overall, Furutaka may feel like a groaner, but it will prepare you for the high tier CA gameplay, and lessons learned in it will be very relevant once you man the bridge of the tier IX Myoko. The next ship following the Furutaka, the Tone, will be yet again a completely different beast in terms of gameplay.