The expertise options gained through the Cleric's Knowledge Domain feature aren't available in the character creation. The two extra languages gained through the same domain also doesn't show.

Moreover, some sections of the Knowledge Domain character sheets mistakenly shows the Life Domain's feature (Preserve Life) instead of the appropriate Knowledge Domain feature (Knowledge of the Ages).

Could you link the character?

I can't reproduce these errors -- I would check and see if you have the actual version of the Knowledge Domain, or if you have a homebrew version. As the Life Domain is the free version on the site, it's what someone would use as a template to make the Knowledge Domain, and maybe they just weren't done yet. You'll be able to tell it's homebrew by looking in the Features & Traits tab, then looking at the subclass traits (so, the specific Channel Divinity, not the general entry for Channel Divinity) and looking to see if it's got a PHB citation next to it or if it's blank. If it's blank, it's homebrew.