The floor in shower

The window box. What to do with this? Pillows? There’s very rusty gold hinge across that needs to be switched out.

Also debating switching out the flooring vs cleaning up the grout. How dated does the flooring look to you?

Ditto what Nancy said above ⬆️

If i were on a budget with this room, I’d paint the green out, clean the tile grout, use some nice big washable rug to hide most of it, and save for a full remodel. Agree that painting gray is going to make you hate the beige tub and tile even more. Don’t do that. You can’t really change the shower step without really tearing into stuff and starting to run the $$$ meter. It will all look a lot better without that green....start there and see how it looks

All you can do is paint the walls.

Save up until you can afford a proper gut job. otherwise, don't waste putting much more into that room.

this should be your goal

The first thing you need to do is to paint. Do not use gray, even though it is a popular color. We have a brownish/pinkish tile in our bathroom that I hated when we moved in. The walls were an old (read: dirty) gold that made the tile look worse. I ended up painting the bathroom and very light cream - BM White Dove. It made the tile look so much better. While I am still not a fan of the tile, it is much more workable for us. It also doesn't look so brown or pink any more - the wall color really neutralized the tile. A pale cream will take some of the edge off the tub and will still co olé net the floor tile. Which, by the way, I suggest you have professionally cleaned and regrouted. You don't need to redo the floor or shower tile for the time being. If you really want to change the color of the tub, you might be able to have it professionally painted. I know people out there will do that, but I have never seen what a painted tub looks like when done, so am not sure of the quality. Definitely, start with paint - if you don't like that, it is an easy and cheap redo.

Also, if you can, get rid of the column.

If you have to step up into the shower, not just step over a curb, then I bet there is a reason that it was not possible (or cheap enough) to situate the drain below the floor level. In other words, there is a reason for it. Is there a basement under the shower? Is it on a slab? These are things that you can try to determine in the years you are saving for the remodel.

You may be able to clean up the hinge and then treat it with Rust Reformer to stop the rusting process. That would leave it blackish in color. You can then point it a metal color of your choice. That should keep it until the remodel.

Green or blue would usually be the choice if you wanted to add color to a peachy beige tile room, but you need a more updated green than the one you have. It is the outdatedness of this color combo that is likely getting to you. If you like warm, rich colors, you could go with a terracotta color on the walls and it will make your tile look nice. A green-blue shade could be nice to contrast with the tile. The safe thing would be a warm off white. Boring, though. I wish I could find you come photos to see, but when you do a search on Houzz for photos with beige bathroom tiles, all you get is whites and grays!

Glass Slipper, Argent, and Wedgewood in this article would look good in this bathroom. So many people no longer like actual color on the walls, though, so you may really disagree. The other colors in the article may work for you, if this is the case. Whatever you try, put the largest paint sample you can get on several of the walls and live with it for a while to see. You can get something like posterboard squares at paint stores that are meant to be painted with the sample paint you can get. Their surface is supposed to approximate drywall better than posterboard.

I also ran into a Houzz Bathroom forum question on a beige bathroom in which Navy was suggested as a wall color. If you like dramatic rooms, this could be nice. SW has a navy as their color of 2020, too. Pantone gives "Classic Blue" and it would work here and even make your cabinets look better. I can see a corner of one.

I agree with all the above -don’t expend a lot of money and effort on a room that needs a major redo until you can do it right.
Paint the green walls a creamy off white, clean the grout, buy some bright towels in a color you love to perk it up. (At least the floor is tile and not carpet!)
A view of the vanity side and a long shot of the room might give you other ideas for consideration. I get the sense you have a fairly high ceiling and that’s why you have the low area over your shower?
Any chance you can get rid of that column or is it holding up the ceiling?
Can you see if the tile floor continues under the window box? If it does, it might be worth trying to remove that entirely before you paint. Good luck!

It looks like a fiberglass or acrylic tub. I am not sure that you can paint those, and even on porcelain that does not flex, most paints chip off.

I agree with picking a paint color that complements, not contrasts with, the existing tiles. Clean the floor grout or use Grout Renew to re-color and re-seal the grout. If you hate the shower floor, look for a complimentary tile and have it re-done. It does not need to be torn out to do so. Your tile guy will add a drain extension and tile right over the existing. I doubt the column is load bearing and it can probably be removed. If not, box around it to square it out and modernize it a bit. Sounds like you have a piano hinge on the box. Change it out or re-paint the one that's on there. Add a pretty patterned cushion. Can you post pictures of the vanity side?

Save your money for a gut job remodel. Don’t do anything but paint it a light neutral color you can live with until you have the money for the remodel.
NO GRAY paint in that room with those fixtures and the brown shower floor.