Need some help here

Recently, I got a new pc and downloaded all my games and such on there, and ultimately me and my wife decided to give my old one to my kid for his birthday. I pulled everything I need off of it and deleted everything else except for Steam. However, I noticed that the save data for the games are still on the old one, particularly for games like fallout and Skyrim. Normally I wouldn’t care but those are the two games me and the misses play all the time and we couldn’t figure out how to delete the save data. Hell, even uninstalling the game didn’t help at all.

My brother told me to just reset the PC, but figured there was no harm in asking on here before I went through with it. If anyone could tell me a way to delete the damn save data off the pc itself would be great, and if worst comes to worst I don’t mind just resetting the damn thing.