Need help on two questions

What term would you move using inverse operations to put this equation into standard form (Ax+By=C)
3x = 5 - 2y

5 by subtracting 5 to the other side
3x by dividing by 3 on both sides
-2y by adding 2y to other side

Natalie wanted to find the y intercept for the standard form of this equation. Here are her steps. Did Natalie make a mistake? If so, which one was her first? If not, indicate that as well.
Solve for the y intercept by substituting 0 for x.
2x + 4y = 20

Step 1: 2(0) + 4y = 20
Step 2: 0 + 4y = 20
Step 3: 4*4y = 20 * 4
Step 4: y = 80

A: Step 1
B: Step 2
C: Step 3
D: Step 4
E: Natalie made no mistakes