"The program is written in Fortran old and worked fine in Windows XP. How to make it work with Windows and the x64 and 10 without overwriting a later version of Fortran?"

Old Fortran 16 or 32 bit? Your best bet is to install XP into a virtual drive (vhd) on windows 10, and continue to use your older Fortran program in XP.

Старый Fortran 16 или 32 бит? Лучше всего установить XP в виртуальный привод (VHD) на Windows 10, и продолжать использовать старую Фортране в XP.