Allahumma Ihdeni Fiman Hadayt
(https://fb.watch/6Y2WgVq0Xa/)
Allahumma Ihdeni Fiman Hadayt, Wa A’feni Fiman A’fayt, Watawallani Fiman Tawallayt, Wabarek li Fima A’atayt, Waqeni Sharra Ma Qadayt, Fainaka Taqdi WalaYuqda 'Alayk, Wainnahu La Yadhilu Man Walayt, Tabarakta Rabbana Wat’alayt.”
اللهم اهدني فيمن هديت، وعا فني فيمن عا فيت، و تولني فيمن توليت، وبارك لي فيما أعطيت، وقني شر ما قضيت، فإنك تقضي ولا يقضى عليك، وإنه لا يذل من واليت، تباركت ربنا وتعاليت.
This means: “O Allah, guide me among those whom You have guided. Grant me safety among those whom You have granted safety. Take me into Your charge among those whom You have taken into Your charge. Bless me in what You have given me. Protect me from the evil that You have decreed, for You decree and nothing is decreed for You. And there is no humiliation for whom You take as a ward. Blessed and exalted are You, our Lord.”
After this, say: "Allahu Akbar" and bow down and complete the rest of prayer like other prayers.
It is good to ask for forgiveness and mercy from Allah at the end of your Salah. You can say this in your own words and in your own language. But it is better for you to memorize some Du'as (supplications prayers) from the Prophet Muhammad (pbuh) in Arabic.