Anything related to equities (including dividends) have risk factors. Company may not pay dividends or may reduce dividends. It all depends upon how much profit they make and how much capital they need for future growth.

On losing capital… dividends come from owning shares of companies (i.e. stocks) … so yes, owning stocks does have probability of losing capital.

On withdrawing capital….. you can sell your stocks anytime you want during market hours. but you may or may not get your original capital back. depends upon the price of the stock at that point in time…

Best Wishes,