What is your goal? To convert PbO2 to PbO? PbO2 is not soluble in water and is a very strong oxidant at low pH. The product, PbO, is also insoluble in water. Commonly, a fine powder of PbO2 is used as an oxidant. Only the surface of solid PbO2  is involved in the reaction.

I ― The Pb(IV) oxide (lead dioxide) can be reductively dissolved in hot aq. conc. HCl, as hydrogen tetrachloridoplumbate(II), while chlorine evolves from the solution: PbO2 + 6 HCl → H2[PbCl4] + 2 H2O + Cl2.

II ― It can be also reductively dissolved to the Pb(II) state when dissolved in hot conc. HNO3 in presence of (e.g.) oxalic acid or H2O2, or of some other conveniently selected substances capable of acting as reducing agents for Pb(IV), but not for the HNO3. Note that in different circumstances, such (added) substances could possibly be generally best seen as oxidants.