Question regarding conjugation of veller

I'm still learning (Cambridge course with Caecilius)[also I'm pushing 30 so give me a break, I started late] and am struggling with conjugation of "to want". If I were to list them it would be Volo, vellas, vellat, vellamus, vellatis, vellant; right? So why is "He wants" translated to Vult as in Deus Vult, and not Deus Vellat? Is -ult a more proper way to say he/she/it wants?