I am surprised that no-one has answered your question as of yet. Well Db and Gb are not hard to find. On any keyboard the black keys are grouped together in a set of 2 and 5. You can spot this set easily. Wehn you see two black keys together, rest assure that you will see 3 more black keys grouped together immediately following the group of two.
In the first group of two, going left to right, the 1st one is called Db this is the note you are looking for. The 2nd one is called Eb. Ok
Now in the first group of three, going left to right, the 1st one is called Gb this is the note you are looking for. This same note is also refered to as F#. On paper it looks different but on the keayboard it's the same look feel and sound. The 2nd one of the three is called Ab and the 3rd one of the three is called Bb. Got it? Ok good.
See that was simple.