Open the Google Play Store on your Chromebook
Search for Roblox
Install the Roblox app
Open Roblox from the app launcher
Sign in to your Roblox account
If the Play Store is not available, enable Google Play on your Chromebook settings
If Roblox is not supported on your Chromebook, use the Roblox website in Chrome
Go to roblox.com and sign in
Join a game from the website if supported
Keep Chrome OS updated to improve compatibility