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How to construct a QPOINTS file for phonon calculations in VASP, and when is it employed instead of KPOINTS during a VASP standard run for phonon calculations? Could anyone also provide the preferred format style for specifying q-points in the QPOINTS file?

The QPOINTS file has the same format as the KPOINTS file. You can use it for interpolating phonon spectra for band structure and DOS.

But i am confused there are two formats for KPOINTS one has regular mesh and other has k points along high symmetry lines used for bands structure.which format should i use?

That depends what you want to do. For a phonon DOS you would use a regular mesh, for a phonon band structure the line mode.

ok I've encountered an issue while attempting to run VASP calculations for phonon band structures. I have prepared the following input files: QPOINTS, INCAR, POSCAR, POTCAR, and KPOINTS. However, when I execute vasp_std, it fails to run. What could be the issue? Could you please review the format of my input files and provide guidance on what might be causing the problem?"
INCAR File
ISTART = 0 ; ICHARG=2
PREC = Accurate
ENCUT = 520
IBRION = 8
NSW = 1
EDIFF = 1.0e-08
NELM = 100
ISMEAR = 1 ; SIGMA = 0.005
NELMIN = 8
ALGO=Fast
LREAL = .FALSE.
ADDGRID = .TRUE.
LWAVE = .FALSE.
LCHARG = .FALSE.
LASPH = .TRUE.
NWRITE = 3
LEPSILON = True
LPHON_READ_FORCE_CONSTANTS = True
LPHON_DISPERSION = True

KPOINTS file
Auto
0
Gamma
16 16 1
0.0 0.0 0.0
QPOINTS File
K-Path Generated by VASPKIT.
20
Line-Mode
Reciprocal
0.0000000000 0.0000000000 0.0000000000 GAMMA
0.5000000000 0.0000000000 0.0000000000 M

0.5000000000 0.0000000000 0.0000000000 M
0.3333333333 0.3333333333 0.0000000000 K

0.3333333333 0.3333333333 0.0000000000 K
0.0000000000 0.0000000000 0.0000000000 GAMMA

Please provide a complete set of input files including the structure. You can also try a simpler system to make the code run faster so that it is easier to try different things. One important thing, you don't specify vaspin.h5 as one of your input files. These are required for phonon band structures. You can also work on the phonon tutorials and make sure that your workflow is correct by reproducing this exemplary results.