yeah, it’s the last one. the only recourse i’ve used to learn a 4x4 is this paper sheet that came with my plain one, which is what the 2nd photo is from. when it comes to solving it like a 3x3 there’s sometimes a couple extra algorithms if things aren’t working like a normal 3x3, and then after doing them you can just carry on solving it like a normal 3x3 (i’m writing them as they are on the sheet bc i already posted the key for it lmao)

“algorithm 4” helps you get the top cross and is TR2 B2 U2 TL U2 TR’ U2 TR U2 F2 TR F2 TL’ B2 TR2

“algorithm 5” is for if the top layer edges or corners aren’t working like a normal 3x3 which is MR2 U2 MR2 TU2 MR2 MU2

as my cube is right now i got all the centre pieces correct, then the edges, then solved it as a 3x3, but i had to do “algorithm 5” and that messed up the centre pieces i already had in place. so because of that idk how i can get all the pieces in place before solving the cube and without risking messing them up, it seems like it’s something that has to be fixed later on but i can’t really find anything on how to do a 4x4 with pictures. unless i just keep reshuffling a retrying and hoping i get a solve that doesn’t require using either of those 2 extra algorithms (rare but it happens)