For Floors: A very quick rule of thumb I use during preliminary design is to calculate 8% of the clear span distance for the depth of the floor structure.
For Walls. A more difficult question to quantify. Looking up Case Studies may give you some good direction.
As @endlessfix notes there are many considerations to account for by the engineer involved. As @gsharp points out, it is good practice to indicate in some manner, that your drawings are not a complete(d) design.