Sacred Citation & SourceAllah says: "Whoever relies on Allah, He is sufficient for him" (65:3) and "When you have decided, put your trust in Allah" (3:159). Tawakkul does not mean doing nothing. The Prophet ﷺ prepared, planned and took precautions, then trusted Allah.
Sacred Citation & SourceHe said: "If you relied on Allah as He should be relied upon, He would provide for you as He provides for the birds: they go out hungry in the morning and return full in the evening" (Tirmidhi 2344, Ibn Majah 4164). The birds do go out: trust includes effort.
Sacred Citation & SourceWith tawakkul, anxiety lessens: you do what you can (study, work, ask, plan), then accept the result as a decree of Allah, with confidence that His choice is good for you. Say "Hasbunallahu wa ni'mal-wakil" (3:173). These are matters of the heart, not of rulings: take what helps you act and ask a qualified teacher if you are unsure.