Project Hail Mary · Andy Weir, 2021
How far is Tau Ceti from Earth in Project Hail Mary?
11.9light-years
Tau Ceti is 11.9 light-years from the Sun. Rocky's star is about 10 light-years further on.
From the book
Tau Ceti is the one nearby star that is infected with Astrophage but not dimming. Finding out why is the whole point of the trip, and it is why the Hail Mary goes there and not somewhere closer.
Grace wakes up in orbit round it with no memory of the journey. The crew slept the whole way. It is a one-way trip by design.
The star positions on the map are real. Each star system is drawn about 85,000 times bigger than the gaps between them, or you wouldn't see anything at all.
See Tau Ceti on the star chart