Not r/gamedev. That place used to be good, but it's turned into a load of kids posting about marketing tactics and how annoyed they are that their unoriginal game clone #456 with "retro 8-bit graphics" hasn't made any money on the app store.
I don't think I've ever felt the need to ask a community for help. I email authors or post questions on people's blog posts if I need clarification on something they're writing about, but largely I don't think there's much a community can add beyond tech support for a specific tool (RPG Maker tech support is a very big section). If you want help learning a specific tool, then YouTube videos are probably the best thing, until you're at a level where you can jettison the hand-holding and just use the tool's official docs for everything you need.
For feedback on a project; you've got everyone here - but it is sometimes best to ask individuals for their opinions and not an entire community. I would probably ask opinions of everyone, but I'd value different people's opinions quite differently.
EDIT: If you're doing something that is niche with excellent search engine queries then YouTube is sometimes pretty good for getting people to find your content and discuss it, give feedback, and support your ideas. My GBA demos on YouTube seem to make people wet themselves with excitement.