Buying my first Property ever, need help

[Eduard Tanasov]

I just got pre-approved for $450,000 from a lender and want to use that on a duplex rental property. Since I currently live with my dad I need to live in one of the units. I really don't like that idea cause I want to rent out both units. So I was thinking of buying a separate house in the $40k-$90k price range, so I have a primary residence, and use about $150-$250k for my rental. I have enough DTI for $450k so it should be fine... right? I haven't spoken to my lender about this yet but was curious is this something possible for a first time home buyer?