Do you like houseplants? Are you ok with taking care of them? If so, then I recommend getting the hardy types of houseplants you like best. If a plant dies, then you can try another type of plant. Plant nurseries have areas with not so much light where the house plants are sold.

The research about houseplants isn't clear. The International Space Station doesn't seem to have plants, and people live there for many months. But NASA has some old research about the benefits of plants. I've attached the article.

There's also research about a special system that uses plants to purify the air in buildings. I've attached that article, too.

There's probably no noticeable increase in oxygen with indoor plants, but there might be other benefits. This was the link I trusted most:

The plant chemistry that releases oxygen happens in the light. It uses chlorophyll and other pigments in the chloroplasts. Indoor light is quite weak, compared with outdoor light. In the dark, carbon dioxide is used to make sugars.

I think the best part about my plants is that they improve my mood, which is good for my health. On the other hand, I have a friend who thinks the plants on my balcony are a terrible idea, because I have to take care of them. Plants wouldn't improve her mood! [Now I have guinea pigs, too; and they improve my mood even more!]