Before changing the main object, you must sure that the modification is to improve your existing business or entering into new business.
For eg: Changing Object clause for Developing the existing business of Cotton Textiles or Changing Object for entering into new business i.e.textiles to IT field.
It there is no change in business activities then you can conduct an EGM and get approval from the shareholders. Then file e-Form23 along with the altered MoA. No other forms are required.
If The business activities are totally changing then you have to ensure that the profit from the new business is more than 51% then you have to change the name of the company from XYZ textiles P Ltd to XYZ computer solutions P Ltd like that.