D is a point on side QR of ΔPQR

False

In ΔPQD and ΔRPD,

PD = PD                                                 [common side]

∠PDQ = ∠PDR                                                    [each 90°]

Here, no other sides or angles are equal, so we can say that ∠PQD is not similar to ΔRPD. But, if ∠P = 90°,

then ∠DPQ = ∠PRD

[each equal to 90° – ∠0 and by ASA similarity criterion, ΔPQD ~ΔRPD]