Head Gasket failure

The Head Gasket

Can fail - as shown by losing water and a white steam trail behind on start-up.

Whilst the best solution is to fit a new gasket, this requires considerable skilled work.

Certainly as a temporary repair, it has been found that  "Steel Seal"  from Halfords can save time and money in at least the short-term.  It is expensive (£40) but beware cheaper versions which may not give the same result.