Laptop boot problem

I have tried restoring my laptop back to factory settings now when I try and turn it on it just says BOOTMGR is missing press Ctrl+Alt+Del to restart what can I do to fix it as it Kees coming up

make / model of machine?
version of windows?

Packardbell and windows xp

Boot files and probably boot sector weren't written by the recovery process.

If you have a floppy drive you may be able to fix it by downloading the WinXp emergency boot disk set (six disks), starting the machine from them to a command prompt, and then running the file winnt.exe from within the I386 folder. That should run a repair installation of windows and correct the problem
Depending on how the machine is set up the file could be in
c:\windows\I386\winnt.exe
or
c:\I386\winnt.exe

DON'T try the similarly named winnt32.exe as that only works from within windows

You can download the boot floppy set from
either
https://www.microsoft.com/en-us/download/details.aspx?id=12934
or
https://www.microsoft.com/en-us/download/details.aspx?id=1000

depending on the version of Windows XP
If you'd told us which version of XP - including service pack level - I could have been more specific
c:\windows\system32\

if you don't have a floppy drive then we'll have to find a way of booting it from a CD. Do you have a windows CD handy?