Possible yes, pratical no. You indicate treated wood. What type? If the treated wood is still damp with the treating agent, it will be hard to paint at all until it dries out. Then you will need an oil based primer such as Kills. Then I would use an oil based porch and floor enamel matching the exterior of the house. Since you asked for opinions, this is mine.

Don't do it. It will be 'white' for about 1 day. There is a reason you rarely see white floors, especially outside.

Don't paint it at all if you can live with the PT look for a year or so. Horizontal wood surfaces do not like 'paint'. It will eventually fail, its just a question of time. A solid color stain will hold up better but will require frequent recoating.

texasredhead is right on about the damp wood. I owned a wooden stair co. for 28 years and we had our share of ext. wood problems and what happens to painted wood. One job we installed railing around a 20' x 20' courtyard filled with flowers. 6-months after we installed $4,000 in materials & labor we were called back because it was falling apart! WHAT! No way I said! Sure enough, it gaps were big enough to stick a pencil in on some of our joints. As Paul harvey would say, now the rest of the story: We installed all of the work unfinished, the painter was to seal & paint it ASAP, he did not, he said it was a week or so (more like a month) after we installed it and by the time he did the wood had already absorbed moisture from the watering system watering the flowers. He sealed in all the moisture that had penatrated into the wood, so now its several months later in the summer heat/sun baking that moisture that had to get out some how, and it did! It looked like it had been installed like 20 years ago, not months. WAfter this we went to presealed wood from then on, but even then on a southern exposure to rain & sun that goes unmainteined will fail! This next customer called us back after 7 years, saying our work was falling apart! NOT AGAIN! They had never touched the area with paint in the 7 years and sure enough all the areas that got full sun/rain etc. was showing the effects but everywhere that was protected still looked great. I did sell them new materials at my cost and they supplied the labor because I would not set foot on that job again. Please, NO white deck floors! Elden