GROMACS is one of the best MD code if you work on biochemical molecules like proteins, lipids and nucleic acids

I' working with NAMD tool, is it a suitable for MD simulations best one sir?

Yes it's a good program for a large size biomolécules system

Do you have any idea about this tool sir? I have some doubts in membrane simulations.

Gromacs

ACEMD on gpus with 4fs time step is faster than Gromacs. I use both depending on the system.

Gromacs for biomolecular simulations is good, has a decent set of analysis codes too. I use LAMMPS for other MD simulations, simple to compile and use, and has decent documentation. The answer to your question really depends on what you intend on simulating.

GROMACS is one of the best molecular dynamics simulation tool.