Tryna find a action/fantasy mawha

Howdy I'm trying to find this webtoon, I remember that the male lead has white hair with purple eyes and he was reincarnated from a Murim world into a Medieval style world and he's the son of a Duke now and he's training these Soldiers by teaching them like new energies from his world and I remember there's a scene where he's recruiting new soldiers and he got sand thrown in his eyes. Please help me find it