Hi Niki. The first step is to start googling images of kitchens that have, say, gray floor tile - whatever you intend to keep. Then collect images you like. Inspiration images can be very useful in helping you determine what you do or do not want.

Since you are not changing your flooring you will need to take them into account, like eam44 mentioned. The wall color you have looks like it goes well with the floor. How about a taupe paint slightly darker than the walls. What other colors do you have in the house that you could use as an island color? I like this dark gray green color from this picture for the island if it goes with what you have. You don’t want to pick some random color for the island.

Pictures of the surrounding areas.

I'm assuming you'll decide if to do the counters based on budget; make a plan, get all your costs ahead of time and then decide which color to consider because you can do things in stages. Your cabinets need hardware regardless, it will look so much more finished than now.