Yes, but the problem is that if I add different columns, it leads to increase in the number of columns. So, I cannot see all data in screen and have to move left and right. I need to see all data in screen to decide based on them.

How are you going to make any decisions when you can't do any analysis? That would be terrible design and you would certainly regret it later.

One can manage dozens of columns easily in a single table. Limiting yourself to the number of columns that you can see on your screen seems to be a bit obsessive/compulsive and is no more necessary than limiting the number of rows in the same way. Since you say that you have a long list of persons in your table, this apparently isn't an issue.

There are ways to manage large tables thus. For starters, you can freeze rows and columns to keep your field headers and employee names visible as you scroll.