Ignore the power-up (unless you really need it) and continue climbing up. Up the ladder, avoiding the Beaks' shots. Get rid of the Screw Bombers and grab the two power-ups. Wait for a Bombomb to fly up from the pitfall and explode, then jump across to the next pillar. You should soon reach an area with pitfalls and pillars. Start heading east, blasting through the Fleas.
Wily's Factory, Stage 4: Boss Rush 2 and Wily Machine Wily's Factory, Stage 2: Boss Rush 1 and Copy Robot