You can’t in practice protect an idea, and it’s most likely you’re not the first to think of it anyway.
You may be able to get a patent for a process, but you’re patent’s not worth much unless you can afford to protect it. Noone will do that for you.
You can protect a brand or trademark, and that can be worth something if it has ‘traction’, particularly if a bigger business wants to get into that market but your traction is blocking them, or if it’s quicker to buy you than build their own (they may have their own competitors on their tales tails so need to move fast).
Strava, Facebook, Ebay, these are all examples. They probably weren’t the first at what they do, and there’s nothing they do that in essence isn’t easy to copy, but doing that won’t work because they already have traction. Everyone uses ebay because everyone else uses Ebay and have no reason to switch.
Your idea is almost certainly doomed to failure.
Do it anyway, it will lead you places you can’t predict when you start.