Answer:
for the first question, the context is necessary in order to answer...
Fat is immiscible (does not mix) with water because fat is nonpolar and water is polar (remember like dissolves like: polar mixes with polar, nonpolar with nonpolar).
soap bubbles by having many soap molecules surround fat molecules with their nonpolar end, and direct their polar ends outwards.
For your second question:
Dirt and oil are nonpolar. When we wash our bodies with water (which is polar) it does not do a good job in removing these nonpolar molecules. Soap, on the other hand, has a long nonpolar end and a small polar end. The nonpolar end of the soap molecule attaches to the dirt and oil on your skin and when the water from the shower head hits the soap, it pulls the dirt, oil, and soap off of you by attaching itself to the polar end of the soap molecule.
Explanation: