To claim this airdrop go to : https://arbitrum.foundation/
And if you did one of the followings :
Bridged funds into Arbitrum One
Conducted transactions during two distinct months
Completed more than 4 transactions or interacted with more than 4 different smart contracts
Completed transactions exceeding in the aggregate $10,000 in value
Deposited more than $50,000 of liquidity into Arbitrum
Bridged funds into Arbitrum Nova
Completed more than three transactions on Arbitrum Nova
You will be eligible to earn a lot of $ARB