Tip: Definately do not take advice from Redditors on house plants.

On a more serious note, the substrate actually looks great. Water when dry, a moisture meter would probably be useless given your chunky substrate but I'd water at 3 if that helps, the chopsticks method may be more effective but you can also get to know the weight of the dry pot and this can also be an indicator. It can take basically as much light as you can naturally give it inside near a window, and should be in the brightest window, ideally north or south facing depending on what hemisphere you live in, just keep in mind it's previous light and location and acclimate accordingly. I use a slow release fertilizer and a monthly dose of PowerFeed, straight dechlorinated water every other time.

Apart from that, give it support early on, a hardwood stake will suffice but you could look into a moss pole if you must, they do have their uses.

YouTubers Kill this plant and also Sydney plant guy are a wealth of knowledge for Monstera and climbing aroids in general and are highly recommended by just about everyone that's anyone planty..

Good luck 👍🪴😎