How can I shift columns based on certain row?

My datatable is below.

and I want to get this datatable

I want to shift row 1, 4 to rcp column, but I can’t find method or logic that I try.
I just know that shifting all row and all column, I don’t know how I can shift certain row and column.

If you know hint or answer, please tell me. thanks.

>Solution :

assumption: rcp column contains "???" that needs to be replaced with the a values from dtl

# create a filter where value under rcp is "???"
m=df['rcp'].eq('???')

# using loc, shift the values

df.loc[m, 'rcp'] =  df['dtl']
df.loc[m, 'dtl'] =  ""
df

    menu_nm     dtl                     rcp
0   sandwich    amazing sandwich!!!     bread 10g
1   hamburger                           bread 20g, vegetable 10g
2   salad       fresh salad!!!          apple sauce 10g, banana 40g, cucumber 5g
3   juice       sweet juice!!           orange 50g, water 100ml
4   fruits                              strawberry 10g, grape 20g, melon 10g