Lenovo doesn't seem to get the point of Stadia. It's offering three months of access to the service's $10 Pro tier if you buy a new Legion or IdeaPad Gaming-branded laptop or desktop PC. Which is nice. But the entire point of Stadia is that you don't need local gaming hardware to play it. So what's the point of tying a promotional freebie to gaming machines? Wouldn't it make more sense to offer free Stadia Pro on a low-cost machine that can't play high-end PC games?
Lenovo announced the promotion today, though it won't go into affect until it's selling laptops and desktops made after April 5th. The offer is valid in all the countries currently supported by Stadia: the US, Canada, and most of western Europe. Any Lenovo Legion-branded laptop or desktop should be eligible, but there are currently only two IdeaPad laptops branded as "gaming" machines, the IdeaPad Gaming 3 and 3i. The IdeaPad Slim 7 GTX comes with discrete graphics card choices, and it's listed under the "IdeaPad Gaming" section of Lenovo's store, but it doesn't technically fit the parameters of the promotion.
If you happen to be in the market for a gaming machine and the Lenovo models strike your fancy, go ahead and redeem the offer. You'll get a few free games every month associated with your Stadia account, even if you never actually buy anything. You can't play them after the freebie ends unless you pay up again, but they stay associated with your account, so go wild. You'll find the offer in the Lenovo Vantage program on new gaming PCs, or go to gaming.lenovo.com.