Is it true that one who fears their parents says, "I have entered upon you with 'there is no god but Allah' and muzzled your mouth with 'there is no power nor strength except with Allah'"? If true, should it be said secretly or openly? And what are the pieces of advice and remembrances for one who suffers from anxiety and fear of exams?

The cure for fear lies in seeking refuge in Allah Almighty, affirming His Oneness, obeying Him, relying on Him, and supplicating to Him. Among the helpful supplications for this are: "Sufficient for us is Allah, and [He is] the best Disposer of affairs," and "O Ever-Living, O Sustainer, by Your mercy I seek assistance; set right all my affairs, and do not entrust me to my soul for the blink of an eye." Among the helpful supplications for facilitating matters, such as exams, is: "O Allah, there is no ease except in what You make easy, and You make the difficult easy if You wish."