I think that kind of simulation time is only possible with standalone software and forcefields. GROMACS/GROMOS or AMBER are the most used. Of course, and this is more important than which forecefield to choose, you should have the necessary GPU computational power. It also dependscon the amount of atoms you want to simulate. More and more universities have HPC (high performance computing) units. Some countries even install central HPC facilities.

Good luck

Thank you very much for the answer. We do have the GPU, and HPC unit in our university, but that too takes a lot of time. I was wondering that, any cloud service can provide a faster solution. I am thinking to use a virtual machine in the azure microsoft and run the simulation there

You could try set it up on a cloud computing platform, like Amazon's. But it will likely cost a lot.

Thank you very .much Patrick Timmons