Point to custom properties value in layout prop

hi, i want to make a layot with prop that are the same as my custom properties min and max value, to get the min value i use this:

min = obj['_RNA_UI'][custom_prop]['min']

now i try to add it to my ui layout, but it dont work, that what i try:

row.prop(obj, ['_RNA_UI'][custom_prop]['min'])

and i get an error that said that he cant find “obj.[’_RNA_UI’]…”
so i try to move the “RNA” part to the obj but it still not work

row.prop(obj['_RNA_UI'], [custom_prop]['min'])

what i can do is only show in my layout the value of the custom prop, but i cant get the other value, this is how i get the value:

row.prop(obj, f'["{custom_prop}"]')