Since others are suggesting x86 instead of ARM, I highly recommend an LG Gram (either 16 or 17) that comes with an 80 Wh battery, and stock Fedora.

With Power Profiles in Gnome set to "Power Saver" you'll easily last more than a day. Standby power is excellent.

LG has other, smaller models as well, but I think they come with smaller batteries that aren't quite as good a balance of power and weight.