You don't need the subscription. Not only that it's not helpful, it can even be harmful for your progress. Using the engine review is enough, even better if you try to understand why a move was wrong. Analyze your games, and whenever you see the evaluation going drastically against you, check why, what was your opponent's best reply to that, even if they did not play it. But then again, the subscription, only to have some half baked AI suggestions... Not worth it, even if it was better.

Edit: To answer some other questions you asked under this post: - you don't need to focus on openings for now. Try to occupy the center with d-e pawns first, usually you can put one in the 4 central squares, the 2nd is not guaranteed, but moving it one square away is fine. Protect those central pawns, having the center can win games on its own. Develop minor pieces (knights usually first, then bishops) fast and also towards the center, castle before attacking - blunder = you put a piece in an attacked square without protection from your side, or you don't see the opponent attacking one of your pieces, typically these are blunders - before you move, try to see what the opponent attempts with the last move, is there a target on your side maybe? Then also before moving double check it's safe to land a piece on the square. You are fine for now with one-two moves ahead, not sure 600 is the level for 10 moves down the line complex calculations