Figure 2-9(a) shows how the queue is filled by a sequence of the form:

1-byte instruction.
2-byte instruction.
3-byte instruction.

Figure 2-9 Filling the instruction queue after a branch.

(a) First instruction has an even address

(b) First instruction has an odd address

The general operation of a computer as outlined in Sec. 1-4 consists of:

1. Fetching the next instruction from the address indicated by the PC.
2. Putting it in the instruction register and decoding it while the PC is incremented to point to the next instruction.
3. Executing the instruction and, if a branch is to be taken, resetting the PC to the branch address.
4. Repeating steps 1 through 3.

The operation of the 8086 follows this basic pattern, but there are differences and some of the operations may be overlapped.

This is page 14.