The project presented below is developed to solve the 15 objectives and challenges that I was able to extract from your precise description and from the chat conversations, these challenges are:
1_Keep the exterior staircase as secondary.
2_Create a Green Wall Wood and polycarbonate pergola. Ensures privacy.
3_Redesign of the garden as a relaxation area with sofa and armchairs.
4_Enhance the garden with plants.
5_Outdoor picnic and grill area.
6_Open and connect the balcony space with the garden, creating a second access to the house.
7_New outdoor space connected to the garden.
8_New corner stove.
9_The old wooden shelf, retrofitted and repainted in white.
10_Create an open living room with large space for kitchen and dining room.
11_Modular kitchen Lube Agnese.
12_New interior staircase.
13_Bedroom for two little girls.
14_Bedroom for two adults.
15_Entertainment space, projector room at downstair.
As a result, In the project, these design challenges are solved. I hope that you like it.