Place a drip pan or other container on the side of the mower with the filler. Carefully tilt the mower so oil drains out and into the pan. Discard the spent oil into a proper disposal vessel. Now slowly pour fresh oil into the mower. For the specific type of oil you need check your instruction manual. Make sure to add only as much as your particular model requires. Remember to let the mower sit undisturbed for a few minutes so the oil settles properly inside the engine.
I know that many people prefer to hose their mowers down with a garden hose. I admit I have done it. Still doing that is risky. If water gets into the wiring air filter or engine you could really do some damage. Hand washing with damp rag is a drag but also your safest bet.
About 86% of the buyers who reviewed the Honda HRX217VKA on Home Depots website gave it four or five stars. Handyman left the most helpful review after using his mower for one year. He noted that its the best mower he is ever owned because of the adjustable speeds for the self-propel controller. He goes top speed and has to walk briskly to keep up. Other buyers remark that the mower cuts well after just one pass and doesnt leave stragglers clumps or lines. One buyer was impressed with how it could even handle unkempt grass over six inches high.