I heard that some routes has like 2 different versions, so its true? If yes, than what routes has them and how to get them
Keisuke's and Jun's routes are fairly linear. There are some choices that lead to different flavor text, but nothing significant.
Shoichi's route has a split into 3 different versions.
To get route Route A you need to choose:
Day 21: Tell the truth / Deny it
Day 22: “What I said?” / “I still mean it.”
Day 22: “Ignore your father!” / “Agree with him for now.”
Day 24: Maybe a little / Not at all
Day 24: I can’t bring myself to stay silent / I need to be quiet
Day 26: Be firm / Be apologetic
Day 26: Keep pushing / Let it go
To get Route B you need to choose "Let it go" on Day 26.
To get Route C you need to choose "Deny it" on Day 21, "Agree with him for now." on Day 22 or/and "I need to be quiet" on Day 24. After that "Be firm" and "Keep pushing" on Day 26.