The Prophet ﷺ used his right hand for getting water for ablution and taking food, and his left hand for his evacuation and for anything repugnant. (Using translation from Abū Dāʾūd 33)
كَانَتْ يَدُ رَسُولِ اللهِ ﷺ الْيُسْرَى لِخَلَائِهِ وَمَا كَانَ مِنْ أَذًى وَكَانَتِ الْيُمْنَى لِوُضُوئِهِ وَلِمَطْعَمِهِ