M1 MacbookPro memory

I am going to purchase a M1 MacBook Pro 13"

Some of the advertising verbiage indicates that the 8gb of ram and 8gb of graphic ram will be used for data. So does this mean 8gb is really 16 or do I need to upgrade to 16gb. I do not do videos or photo editing but work with excel and powerpoint a lot. the 2015 MacBook pro I have has 8gb ram in it and I am always slowing down about to run out of memory.

What is best suggested route.

Thank you.