I desire a Surah or a supplication to remove my intense distress and anxiety regarding marriage and the future due to my delayed marriage, so what do you advise me?

All matters are in the hands of Allah, and He is the reliever of distress. When afflicted with a calamity, one must resort to Him through supplication. He has promised to answer, but He may save it for later or avert evil with it. The supplicant should not despair, for Allah loves those who supplicate persistently. One should seek out times when supplications are likely to be answered, such as the last third of the night, the last hour of Friday, between the Adhan (definition) and Iqamah (definition), during prostration, and after the final Tashahhud (definition).

The woman should be patient and seek reward from Allah, remembering that a delay in marriage may be for her own good. She should frequently remember Allah and seek refuge from Satan, and supplicate with the authentic supplication: "O Allah, I am Your female servant, daughter of Your male servant, daughter of Your female servant, my forelock is in Your hand..." for this removes worries and sorrows.