The supplication that the Prophet (ﷺ) made very frequently is this:
اَللَّهُمَّ آتِنَا فِي الدُّنْيَا حَسَنَةً وَفِي الْآخِرَةِ حَسَنَةً وَقِنَا عَذَابَ النَّارِ
Pronunciation
Allaahumma aatinaa fid-dunyaa hasanatan, wa fil-aakhirati hasanatan, wa qinaa ‘adhaaban-Naar
Meaning
O Allah! Give us in this world that, which is good and in the Hereafter that, which is good and save us from the torment of the Fire. Whenever Anas (RA) had to supplicate he made this very supplication, and whenever he (intended) to make another supplication he (inserted) this very supplication in that.
Source: Muslim: 2690
Read the hadith
حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا إِسْمَاعِيلُ، - يَعْنِي ابْنَ عُلَيَّةَ - عَنْ عَبْدِ الْعَزِيزِ، - وَهُوَ ابْنُ صُهَيْبٍ - قَالَ سَأَلَ قَتَادَةُ أَنَسًا أَىُّ دَعْوَةٍ كَانَ يَدْعُو بِهَا النَّبِيُّ صلى الله عليه وسلم أَكْثَرَ قَالَ كَانَ أَكْثَرُ دَعْوَةٍ يَدْعُو بِهَا يَقُولُ " اللَّهُمَّ آتِنَا فِي الدُّنْيَا حَسَنَةً وَفِي الآخِرَةِ حَسَنَةً وَقِنَا عَذَابَ النَّارِ " . قَالَ وَكَانَ أَنَسٌ إِذَا أَرَادَ أَنْ يَدْعُوَ بِدَعْوَةٍ دَعَا بِهَا فَإِذَا أَرَادَ أَنْ يَدْعُوَ بِدُعَاءٍ دَعَا بِهَا فِيهِ .
Qatada asked Anas which Supplication Allah's Apostle (ﷺ) frequently made. He said: The supplication that he (the Prophet made very frequently is this:" O Allah, grant us the good in this world and the good in the Hereafter and save us from the torment of Hell-Fire." He (Qatada) said that whenever Anas had to supplicate he made this very supplication, and whenever he (intended) to make another supplication he (inserted) this very supplication in that. [Muslim: 2690]
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset