The Life domain is the only domain offered for free as part of the Basic Rules. All other domains are available as purchases from the books they were published in. You can buy the whole book, just subclasses, or just the single subclass you're interested in. In many cases it will be worth also doing the same with spells, some subclass spells also require a purchase.
On my profile the Life domain is the only available domain. Does anyone know why the others aren't available?
The Life domain is the only domain offered for free as part of the Basic Rules. All other domains are available as purchases from the books they were published in. You can buy the whole book, just subclasses, or just the single subclass you're interested in. In many cases it will be worth also doing the same with spells, some subclass spells also require a purchase.
Birgit | Shifter | Sorcerer | Dragonlords
Shayone | Hobgoblin | Sorcerer | Netherdeep
So if I have subscription to D&D Beyond I still have to purchase these other things?
Yes. Subscriptions do not provide access to WotC's published content.
Birgit | Shifter | Sorcerer | Dragonlords
Shayone | Hobgoblin | Sorcerer | Netherdeep