As we have discussed earlier, Microsoft Office is a paid software that means you can't get its features without paying. You have to pay to get complete access to the features. Regarding that, we are here to help you. We have provided you lots of product keys that allow working with no ease. Without a general serial key, you are not allowed to get all features of any paid program. However, lots of software allows trial versions to run on your system without a product key in a certain period. You can use Microsoft without any verification in that period, but when the period is over, you have to activate it.