It looks like they are recessed fluorescent fixtures that have been framed in. It's well done for what it is. You have a couple of options:

If you don't like the feel of the lighting (fluorescent light often feels grey), then you can pop out the covers and replace the fixtures with led lights. Then pop the covers back on and you're done.

If you don't like the plastic covers, there are other patterns that you might like better.

If you don't like the large rectangles on your ceiling, then you've got a fair bit of work to do.

• - First decide what you would like.
• - Then the covers and trim need to be removed.
• - Then the fixtures need to be removed.
• - Then the junction box needs to possibly be moved to suit your new fixture.
• - Then the ceiling needs to be drywalled to cover the holes.
• - Then prime and paint the ceiling
• - And finally install the new fixture

search 'how to remove fluorescent light boxes' . tons of videos and how to's along w/ideas.

with all of those other capped holes in the ceiling, I'd say a pro should come in remove any electrical boxes that aren't being used and properly patch and cover the holes by refinishing the ceiling.