Is it permissible for a person who has recently embraced Islam, and whose parents prevent him from seeking knowledge out of fear of extremist groups, to combine prayers for this reason?

Firstly: Seeking Islamic knowledge and adhering to the Sharia protects one from extremism and excessive rigor, whereas ignorance leads to them, as Ibn Hajar said about the Khawarij.

Secondly: It is not permissible to combine prayers without a legitimate excuse. There is no obedience to parents in preventing prayer, and the son should pray secretly if compelled to do so.

Thirdly: Exposing the thigh and lengthening the garment (isbal) are matters of scholarly disagreement. The Sunnah is to cover the thigh and avoid isbal, and adhering to this is not considered extremism.

Fourthly: Listening to music is Haram by consensus. As for hearing it unintentionally, there is no sin in that.

Fifthly: It is not permissible to possess three-dimensional statues of living beings, and there is no obedience to parents in this matter. If they place them, there is no sin upon the son for sitting with them while disapproving of it in his heart.

Finally: The young man is advised to be gentle with his parents, increase his righteousness and kindness towards them, and explain rulings to them gently. Filial piety might change their stance and make them understand his religious commitment.