Let's break this down. We're going to add 63 and 2001 together.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

Step 2: We'll start by adding the digits 6 & 0 in column 2 and get 6.

Step 3: We'll start by adding the digits 0 & 0 in column 3 and get 0.

Step 4: We'll start by adding the digits 0 & 2 in column 4 and get 2.

So, 63 + 2001 = 2064.

