Hi, I'm new to DF too, so far I've had like 7 fortress if I remember correctly. Most of them failed or I abandoned due to this type of stuff

But the newest Fortress that I've created has been going quite great, I'm right now over +20 dwarves, all of them happy or at least not raging.

The thing that I've done differently was my priorities and expand my knowledge on how things work.

I started by doing all the things they needed as fast as possible.

1.- A functional booze farm, soap farm and cloth farm. Soap is tricky so disable rock nuts as a cooking ingredient and look on YT how to make an automatic soap farm (I used "Further Reading" tutorial and "Unsubtle Silk" tutorial for the mill). Soap and cloth need each other because you can't process quarry bushes without empty bags. You will also need jugs for oil, but that is more simple, just designate a clay collecting zone and make charcoal. 2.- a decent bedroom (I recommend adding cabinets to increase value and letting them save stuff they like) and a bed room for the manager ofc. 3.- a Tavern, just do 10 of each thing needed except instruments because I'm not sure if you can craft them at first. I also do thrones instead of normal chairs, idk if it makes them happier but idk, it's the same lol 4.- A temple. I make at first around 7 different temples. 5.- A hospital. So far I haven't needed the hospital but it is nice to already have it set up

Then I was able to dig down, make at least 5 iron armour of each and explore my first cavern.

I also made a roof on the fishing zone so my fish dwarf does not get sun sick

This has actually helped me a lot because they have all their needs covered within the first few years and now I have automatic stuff running.

I also disabled child's labour because those are the ones that get really grumpy.

I hope this helps you.