Ertugrul (ارطغرل) is a Turkish word. In Turkish, "Er" (ار) means man or brave, and "Tugrul" (طغرل) means eagle or a brave bird that strikes. Accordingly, "Ertugrul" means a brave man or eagle-like person.
It is permissible to use the name Ertugrul. However, since its correct pronunciation is not easy to render in Urdu, it is better to choose a name from among the names of the Prophets (alayhimus salam) or the Sahabah Kiram (ridwanullahi alayhim ajmain).
Allah the Almighty knows best.
Darul Ifta Al-Ikhlas, Karachi.