Request Time off or LOA?

Hey guys so I was brought back on from seasonal to permanent and I’m happy! I do thought know my family will be going on vacation to Europe in June for the entire month into July. Should I submit the entire month off in myTime or do I have to do a Loa IF i can even do that for a vacation? If I mention this will they just fire me if I can’t work for the month? I’m 100% not missing this lmao