#for multiple columns
min_vals = df[["A","B","C"]].min() #can add how much ever columns
max_vals = df[["D","E","F"]].max() #can add how much ever columns
#for single column
min_val = df["Column"].min()
max_val = df["Column"].max()
#to refer to all columns
min_val = df[:].min()
max_val = df[:].max()
max_value = column.max()
max(df.max(axis=1))