Is commitment to an Islamic group an individual obligation, like prayer and fasting? And is it permissible for any group under occupation to cancel jihad?

Adherence to a specific group is not an individual obligation (fard ayn). Rather, Muslims are obligated to support their religion, work for its service, and cooperate in righteousness, piety, and brotherhood. Collective action is permissible and desirable if loyalty is to the truth, and not to a person or a slogan, as that is characteristic of the people of innovation (Ahl al-Bid'ah). No group is permitted to abolish jihad, for it remains until the Day of Resurrection.