We can solve this together! We're beginning with 999906 and removing 9397 from it.

Step 1: We'll start by subtracting the digit 7 and the borrow 0 from 6 in column 1 and get -1.
We add -1 to 10 and get 9 as the first digit of the result.

Step 2: We'll start by subtracting the digit 9 and the borrow 1 from 0 in column 2 and get -10.
We add -10 to 10 and get 0 as the next digit of the result.

Step 3: We'll start by subtracting the digit 3 and the borrow 1 from 9 in column 3 and get 5.
5 is the next digit of our result.

Step 4: We'll start by subtracting the digit 9 and the borrow 0 from 9 in column 4 and get 0.
0 is the next digit of our result.

Step 5: We'll start by subtracting the digit 0 and the borrow 0 from 9 in column 5 and get 9.
9 is the next digit of our result.

Step 6: We'll start by subtracting the digit 0 and the borrow 0 from 9 in column 6 and get 9.
9 is the next digit of our result.

So, 999906 - 9397 = 990509.