I was looking into buying a road bike. I have been doing some research and I understand a little bit better about components. I was looking at the trek 1.1 but I saw a generic gravity liberty 1. It actually has better components than the trek 1.1. trek 1.1 claris. gravity liberty sora. Both have carbon fiber fork. the price is 419.95 for the generic and 800 for the trek one. What are most important components that I need to look into buying a road bike? Is a frame from a brand like Trek better than a frame from a brand like Gravity? .
Both bicycles have similar components (the Gravity slightly nicer drivetrain, but with a cheapo looking seatpost, etc) and are manufactured in similar facilities in China or Taiwan. The Trek will be set up and fitted by your local bike shop, which will be very helpful if your local bike shop is competent (some aren't).
The Gravity will be set up & fitted by you unless you can find a bike shop to pay $50-$150 to do that work for you-- many won't want to do that work on a bike they haven't sold.
My girlfriend has a Gravity that she's used as a commuter for the past two years in addition to some touring & road rides, and it's done well— it's a perfectly competent cheap bike.
If you yourself were skilled at working on bikes, or have a friend who's willing to help you fit & assemble your bike in exchange for some beers, you'll get a much better value out of the Gravity. But since it sounds like you're not in that situation, and it's fall when bikes go on sale, you'll probably do better buying a Trek/Giant/whatever from a good bike shop on clearance.
If you dont have much experience with a bike setup and maintenance, then get a old-stock bike from a local shop. The amount of money you will pay extra will be equal to the money spent for putting the online-bought bike together. Also local dealer will be able to find you proper bike size - just because you are X inches tall, doesn't mean you should by Y-sized frame. Local dealer will be able to let you test ride different sizes and adjust the new bike to fit you the best. You can search YT for fitment videos. It's not an easy process and takes time.
That Gravity bike seems like easy entry-level road bike. But it's limited - if you want to upgrade its components in future, you will have to change whole set, and that's major expense (ie. new Shimano 105 set will cost you $500 on ebay).