Is there any method for us to be able to create a continuous simulation running from a previous given result?
For example, if one simulation for top surface drop already completed and would like to drop with bottom surface with the result from top surface directly link for the new simulation (drop bottom surface), can it be done?
You can perform a restart analysis. See this page in the help documentation: "Help > Simulation Mechanical > Setting Up and Performing the Analysis > Analysis-Specific Information > Nonlinear Analyses > Analyses Parameters > Advanced Settings > Perform Restart Analyses".
However, I believe you will essentially need to simulate the drop of the part on its top, pick it up, and drop it again on its bottom surface. Or something like that. (With my sense of humor, I would drop it "up" so that it lands on its top, then reverse the gravity direction so that it drops "down" onto its bottom surface. Results wise, it is the same. The software doesn't care which direction the parts "falls".)