One thing you will learn real fast in this hobby whether you choose to continue in it or not is SW vs FW is so much more rewarding but so much more frustrating at the same time.
Visually SW is so much more stunning and captivating and so much more demanding depending on how anal you choose to be with upkeep compared to FW.
The two biggest pieces of advice I can give is first patience is a virtue in this hobby never rush and do your homework especially when it comes to fish and inverts many species are specialized eaters and others can outgrow smaller tanks in no time
www.liveaquaria.com is sort of the bible on fish and inverts
Secondly use this forum for resources and advice. There are a lot of SW forums out there but many posters will steer you with bad advice on those forums. Canreef members have had some very ribald discussions but nobody here will ever try to steer you wrong.