BTC Blockchain WALLET ACTIVITY Although I can see all transactions in my "wallet activity" I pasted my wallet address into Blockchain Explorer expecting to see the history of transactions in that wallet. It directs to a page that shows no transactions....what am I missing and how can I see this info on the Blockchain?
Many wallets that are designed to facilitate an easy user-experience will simply display one receiving address at a time. Once that address receives funds, a new address will be displayed. This helps adhere to the best-practice of only using an address once, which is very important for privacy.

With that in mind, if you're just copying the receive address as a means of looking up your funds on a block explorer, then it is expected that you'll be shown an address with zero balance. To view your addresses with a balance, you'll need to look up the receiving addresses of your past transactions (and, the change addresses of those transactions, if you've sent any BTC out). 

Note: when you look up addresses on a block explorer, you are giving information to that service: for whatever reason, you are interested in that address. This can be a privacy concern, as the block explorer service can keep logs of devices/ips that query the service for specific addresses.