New to the game - Is there a site to see the Community recommended support gems to use on a skill?

poe.ninja

Welcome!

Now that you are here, there are loads of tools to use. If you are really new to the genre, I would recommend https://mobalytics.gg/poe-2 as a good source. Try to find a build guide that is what you are doing and see how they did it.

I am not saying you have to follow builds, but until you get familiar with the game, they can really make a huge difference in your experience.

https://poe.ninja/ has a great deal of information, but not much in the way of explaining things for new players.

https://poe2db.tw/us/ is a great place raw data about skills, items, etc.

Poe.ninja - it's just a website where you can see the top players in each league and it has a lot of detail on items, prices, etc

Mobalytics or maxroll - these are just build guide websites, if Poe ninja is hard to digest these will be easier.

I mean, build guides are there to guide.

Probably easiest thing to do is look at a couple guides and choose what you want from them. You can scan poe.ninja to see what people are using as someone else suggested but many/most of the endgame setups are unattainable and/or pretty suboptimal for leveling so it might be less informative than one would hope.

As others have said, guides are a good start. Just keep in mind though, lots of supports are used in tandem with certain uniques. It’s not always the case, just something to watch out for.

Build guides generally tell you if they do have stuff working in tandem though.

poe.ninja as someone, probably quite a few, I use build guides as what they should be a guide not a rulebook. Following a guide too closely (gear wise at least) is a bad idea imo as you can't control what you get on league start. Sometimes I'll ignore paths/nodes to shore up something I'm missing. It took me quite a while to get here though.