The main intent of the design is to convert the existing garage to an apartment for 2 with a guest room. I have attached 2 option for your consideration. Both the proposal fulfills your design requirement. I have explained each of the proposal individually here.

Option 1- no internal wall has been disturbed
• The main entrance to the apartment has been shifted to the right, where now is an existing window.
• The living room is planned on the extreme right. This is done to connect your living room to your daughter place.
• The guest bedroom is attached to living room.
• In the middle is the kitchen to make is easily accessible from the master bedroom and living room.
• Next to the kitchen is common toilet.
• The dining area is located at the left of apartment.
• Form the dining area you go to the master bedroom.
• Master bedroom has an attached walk-in-closet and toilet.
• The master bedroom can also have sliding glass door in the existing opening for easy access to lawn.
• The apartment is carefully planned to bring natural light and ventilation in each room. The plumbing is all kept near each other to reduce the cost of the pipes.

Option 2- with an internal wall removed and an iron beam is cast in place of it to provide structure support
• The main entrance to the apartment has been shifted in the center, where now is a existing window.
• The living room is planned in the middle of the apartment.
• Near the entrance is the common toilet on left & coat hanger on right.
• The guest bedroom is planned near the living room.
• The kitchen is placed on the extreme left with an external opening for outdoor dining (optional)
• The dining is located in between kitchen and living area.
• The master bedroom is kept on the left with an attached toilet. It also has a study area & the door to your daughter place.
• The apartment is carefully planned to bring natural light and ventilation in each room.

I have also attached few reference images of iron beam for your consideration. Feel free to contact me for any further assistance.
Thank you