can someone explain how i unlock all routes? also is there a guide to follow?
Basically, there are two routes for each girl, a love route and a lust/NTR route. The love route choices are indicated by heart icons; if you get a choice with no hearts, it doesn't affect the route, and if you pick even one choice that isn't the heart icon, you get locked on the lust/NTR route. The best way to go about things, if you want to see all the content, is to play the love route first to completion, saving at each choice; at the end of the love route you'll have a scene with the girl. If you want to see the lust/NTR scene instead, go back to the last choice and pick the non-heart option.
The love route for each act 1 girl (Ursula/Ada/Rachel) unlocks a specific character for act 2 (Alana/Miho/Powell, I
think), so you need to do at least one love route to just get to act 2 (if you do all lust/NTR for act 1 girls, you get an early game over). Same idea applies for act 2, play through story on love route to get those scenes, then go back to last choice before the scene and pick the non-heart option to see the lust/NTR scene (if you want). Do that for act 3 as well and you've done pretty much the entire game.
There is one character (Lana) who has a route that begins in the arcade rather than at the school (act 1) or restaurant (act 2); you'll start it by cheating at the arcade game. There's also some other characters that have scenes and/or small routes (Felicity has a small route in act 2, Gloria has a small route you can do if you get the TV from Ada's love route, Powell's daughter Clarice has some scenes, Albert has a scene, there's a homeless girl Nikki that you run into in the city/around town that eventually leads somewhere).
That should cover all the routes and pretty much all the scenes; specific endings or scenes you might not unlock unless you do specific things, but you can probably figure that out through playing, and if not, feel free to ask later on.