Blockchain / Bitcoin / Previous address / Next address New to learning about the Blockchain ...

The Blockchain requires a Token for use. It is my understanding that the Token (or rather the code implementing the Token) is responsible for filling up the Data portion of a block (that is to be added as part of the Blockchain).  Is this correct? 

If so, this means that what exactly goes into the Data area of a block is dependent upon the Token that fills it.Does that mean that Bitcoin is a type of Token?

In the Block (that sits on the Blockchain), there is a Previous address and a Current address. The Previous field and the Current field is used to support the Linked List structure of the Blockchain (with the Previous address pointing to the Previous block in the block chain and the Current address being the actual block id of the Current block).

Does the Current address of the block take into account the Data area (or contents) of the Current block? My understanding is that the Current Data area of the block would hold Merkel Trees - and - that the root of the Merkel tree is somehow incorporated as part of the Address of the Current block.

TIA
You're confusing a few of the terms here. The "data area" of a block contains transactions. Transactions generally redefine Bitcoin ownership by signing over funds from one owner to another. "Token" doesn't seem well-defined to me, so I'm not sure whether a bitcoin would constitute a "token" in the way that you think of "token".

Blocks are identified with the hash of the blockheader, not an address. A new block points at its parent block by including the parent's hash in their blockheader. The blockheader's hash covers the content of the block by including the Merkle root of the transaction tree which commits the block to specific set of transactions. 

I've written a bit more about how the blockchain works here:
Can someone explain how the Bitcoin Blockchain works?