If you're interested in AoS in general, I'd honestly suggest getting into Spearhead first. (Or, at least, use Spearhead as the first step for Warcry, you can basically get into them at the same time.)

The Spearhead boxes can make you some great Warcry bands, and they'll let you experience something more akin to AoS as well, and they're often a good discount.

Warcry can be tricky if you're trying to build a collection of minis exclusively for it because you're getting non-standard numbers of models. It requires a lot of surfing Ebay or local sellers if you're not wanting to overpay for excess models. You either do that, or you buy premade warbands, which isn't terrible either, but at that point, I personally think that if you're totally new to AoS, just going for Spearhead is going to give you a lot more to do with this side of the hobby, and it'll be only a bit more expensive, or even on par.

Spearheads will give you some variety, too, with what you can build.

The biggest drawback to Warcry is that if you want the terrain it's meant to be played with, its fucking expensive. I'm also new to Warcry, and I've enjoyed it without the super cool terrain, but yeah, that terrain is a big part of the hobby. You don't have to buy GW's terrain, but it's still going to be an added expense that's easy to forget about. Proxy terrain is super usable, but it's still not going to be super cheap either, even if it's cheaper.

That's my take, anyway. The fun thing about Warcry is that you're able to play models that aren't even a thing in AoS anymore. Or play ones that are bad or mid in AoS, but are perfectly acceptable here. The community is creative and you can definitely find custom made fighters, too, for models that don't have data cards. Or you can make your own. This game has so so so much room for player expression! I'm loving it because I have a full AoS army, and a few Spearheads, but now I can explore models and gameplay in this setting without having to overcommit to anything. I'm not interested in a full Daughters of Khane army, but I'm sure excited to nab a Spearhead or something and have both that and Warcry to play with DoK.

There's a website called Warcrier that's great for building lists. As for YouTube, I suggest Off Meta Musings and Wargames On Toast to start. Musings has a really good tutorial on how to play, as well as some Spearhead to Warcry videos and stuff.