I need clarification on moving BTC to another wallet First off-- I am a total newb-- just bought btc today. Its sitting in a DEX wallet and I want to move it to another wallet. Which key do I use to identify the new wallet when I want to send?  Are they asking for the set of words or the jibberish key?
I would expect the "jibberish key" is the address in this case. The set of words is known as a "seed", and is used to back up all the private keys in your wallet. NEVER share those words with anyone, anyone with those words can spend all your bitcoins.

"Normal" bitcoin addresses start with a 1 and are usually around 34 characters long, made up of lowercase letters, uppercase letters and numbers. An example is 1BvBMSEYstWetqTFn5Au4m4GFg7xJaNVN2. Some bitcoin addresses also start with a 3. More recently a new type of address has begun being used, starting with bc1, but its unlikely you will see these commonly for a while. These addresses are all anyone needs to send transactions to you, they will never need the seed words or the private keys or anything else. Keep those safe and to yourself.

Some wallets such as blockchain.info also use a wallet identifier which is made up of numbers, letters and dashes (-), that is also for private use and does not need to be shared, it is not an address.