Look at what you can do now:
Resource tracking DP (Red Green Towers): j = answer after steps using of some resource.
Grid DP (Grid 1): = answer for cell at row , column .
String DP (Edit Distance): = answer comparing first characters of one string to first of another. The same 2D table structure, but the indices mean completely different things. Recognizing which pattern fits your problem is the key skill. In the next section, you'll dive deep into Knapsack problems, a special case of resource tracking DP.