Unless you have an atypical skillset, I'd suggest building your own spreadsheet. You'll learn more from thinking about making it than you would by filling in someone else's.
Things I like on my spreadsheet:
A summary of the last few years' spending to compare with the stash (e.g. so I can see that I could retire now if I didn't have holidays or wine).
Estimates of net worth as an adult to see progress (this is great for my motivation).
Each type of account (current, SIPP, work pension, ISA) is tracked separately with the ages that I can access them on a different tab.
Another tab where I can play with my assumptions (growth, inflation, pension access age, pay rises).
Lots of charts.