how get all data in html page with c#

I want to save all the information and sections that come as text on a html page via #c

I have ideas for my mind, but I do not know how to implement it There are two ways in mind to take one whole page html and remove tags

Second, separate reading of each tags and extraction of words

Thank you very much for advising me how to do this with c #

Meanwhile, I do not want to use ready-made libraries