You won't get much help without a scaled floor plan. Also, this is a U.S. site and dimensions should be in feet and inches, not meters.

Fanny, my sympathies! That is indeed a sad-looking bathroom.

Interim suggestion: Each person in the home has their own bathroom caddy, which they bring to the bathroom for use, and repack fully and remove when leaving the bathroom. It's an extra step, but it will eliminate visual clutter until you can finish remodeling, and incidentally make the bathroom easier to keep clean.

For the floor-plan: All recent computers, phones, and tablets that I know of will do an Imperial to metric conversion or vice-versa for you instantly. It can be annoying that US-based people aren't willing to do the conversion themselves, but we are behind the times so please forgive us. I freely admit that I can't do the conversion without an electronic device, but since I use an electronic device to access Houzz, I was able to learn that …

2 m = 6 ft, 6.74 in.

1.7 m = 5 ft 6.93 in.

When making your scaled floor plan, including measurements of both types will help anyone viewing the plan, whether they are used to Imperial or metric, to help you that much more quickly.

First , I would want to know the source & remedy for the mold issue. That would be my priority.

I think a gut job is a must since that will uncover the mold issue. Waht is in the cube behind the

toilet ? DO the rest of famil all shower or still like atub? The reason I ask is at 4 there is going to be a change in bathing soon and often at that age the shower becomes fun.. Storage is awhol other issue and honestly will not happen in thta space prbably. I had Interenational students for years and they all had a caddy for the bathroom I hate a dozen shampoo bottles and body washes sitting out. Even the little one can have a caddy with bath stuff and maybe even a toy or two.. We lived for a long time in a one bathroom home with 3 boys and us . Not ideal but doable .Waht is under the counter where the cabinets are ? I think once you gut the whole thing you might find spaces that are hiding now . We do need that to scale plan but IMO draw it after the whole thing is ripped out. and then you and we will knoew exactly what is there. The big issue is what will you use foor a bathroom while this gets done ?

More info to include:

- Are you limited as to where you can place a fan that can vent outside? That is what you will really need to help with the mold problem.

- How are the rest of the rooms in your home heated and how is this one heated?

- Do you want to continue to have a tub or a walk in shower?

- Until you resolve this problem: It looks like you have functional windows. Do you crack them open for ventilation? Do you squeeze the walls after you bathe? Do you hang your towels outside of this bathroom to dry? Have you used any kind of desicant to help absorb moister in the room? I have a bathroom with terrible ventilation and no window. Doing these things has helped cut down on the moisture and humidity.

The space needs to be gutted. I see no quick fix for all the problems you mention.

Do you have the budget to do it? If, so, consider getting a construction site bathroom.

Once you see it down to studs you will be amazed at what you can do with that space.
Read more at: https://www.viptogo.com/construction-restroom-trailer

Back to the bathroom reno. You don't need a tub. Outfit the shower with a seat, and hand held shower spray. Line the wall with double sinks and a large mirror. Where the tub is, replace it with washer/dryer, storage. Just some ideas to suggest to your contractor. It will be a financial investment, but worth every penny should you sell.

following along

Not much info, no budget given, but here's an idea...