Superstar From Age 0 - Chapter 640:

Cheng Yan transmigrated only to end up in a medieval Europe like world, becoming Roland, a Royal Prince. But this world doesn’t seem to be the same as his former world, despite some similarities. Witches are real and they actually can use magic?

Follow Roland’s battle for the throne against his siblings. Will he be able to win, even though the king already declared him to be a hopeless case and with the worst starting situation? With his knowledge of modern technologies and the help of the witches, who are known as devils’ servants and are hunted by the the Holy Church, he might have a fighting chance.

Now, let his journey begin.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

Liu Yuan is a good game player, especially in the MMORPG Upper Center. Just as he succeeded in gaining the favorability of all the possible characters in Upper Center, he transmigrated. To where? Oops, he transmigrated into the game he was playing.What he saw was a pretty girl. She wept incessantly, failing to notice Liu Yuan’s unusual behavior. She looked up with teary eyes and said in a firm way, “Mr. Junxuan, I will not marry him. I wish to be with you for the rest of my life!” Junxuan… Wasn’t that his username in the game?

“Here's what happened. I was in a desperate situation when I accidentally encountered a dragon. It told me I was a martial arts prodigy and said it would teach me the Dao of Immortality…” “This excuse for skipping class and cultivating in secret… is that seriously the reason?” “I don’t care whether it’s human or not, what matters is that the dragon said: ‘If you want to become strong, kneel and call me Master.’”