I’d like to achieve atleast 10+ players at all times consistantly.
I’m not sure how I can do this I dont know whether to advertise or sponsor the game at all.
If anyone has any advice or tips I’d really appreciate it.
This is the Obby. Escape The Noob Obby! - Roblox
As an obby maker myself, best thing you can do is to advertise or sponsor the game. If you can’t do that, ask some friends to invite other people.
To achieve this you need to get a player base, a player base can be very hard to achieve with an obby. To achieve a player base on a obby you need a) constant updates, b) lots of content and c) lots of stages. Enough stages and content that the player will come back to the game to achieve as much as possibly, rebirths are a great way to do this.
For an obby to work well with a constant flow of players it will take a lot of time and effort.
A couple things that could get more players:
Obby games are hard to get popular due to the little scripting and overused levels. But, if you think your game is truly unique and has the ability to get popular;I would do one of the things above. Good Luck 
maybe you could send the link to your game to all your roblox friends (there’s an automatic way to do this in roblox studio), that’s how I got 1k visits on my game x-ray, which was just a showcase of the new videos feature in roblox! tell your friends to share it with their friends and tell them to tell their friends to share it with more friends and so on and so on!
Spending robux for ads on a basic obby game is a waste imo