Apparently, its way more than my invested capital and changes in amount live. Is this what my investment is worth at the moment? If so, why cant i take/claim/sell it?
If you refresh your account balance page after 2 or 10 seconds, you will see a different value. I believe you will see different balance as price will not stay at the same price over time. It is more truth if your portfolio has a few coins, not only one. The more coins you have in your portfolio, the probability to see they have unchanged prices after 5 seconds is smaller and almost impossible.
You can sell your coin with orders on the exchange order book. Fees for your exchange orders will be charged different for taker and maker fees. If you do a Buy now or Sell now, you will be charged higher fee as you are a taker.
https://www.cryptowisser.com/exchanges/