Cpctc
No worries.
Here's a tweet from GOS listing the app they will fork (copy) and improve to be the official GOS gallery app.
You could try this one.
https://xcancel.com/GrapheneOS/status/2034395047513162039#m
Why
The above tweet mentions "badly aged AOSP ... app"
I don't think there are many sources about them being: slow, lacking features, and possibly buggy
I've only seen GOS essentially state they aren't good and old, get new ones.
calendar
GOS technically has a calendar app because the system needs a calendar database. However, you can't open the calendar app. You must get a new calendar app.
These fossify apps are a good start. Maybe later you'll experiment with other apps after getting settled.
https://www.fossify.org/apps/
There are links to download these from fdroid or the play store.
For editing a picture, some people like to use markdown from the "app store" app.
Or there is another photo editor on stockOS that ive seen people talk about getting from the play store but I can't find it.