Disclaimer: I'm newbie in vhdl.

I'm working on an assignment that aims for creating a logical processor 
that makes bit logical operations on 8-bit operands. Unfortunately I'm 
lost when it comes to connecting bits of the project and I can't move 
forward due to that, as vhdl is a dark territory for me.

Could someone help me connecting the parts of this processor so I can 
move forward?

Below blocks with IO and their purpose described:

List of blocks:
register_block
steering_block
calc_block
router
display

1. Whole processor block:
INs:
CLK - clock
RST - reset
EXEC - execution of calculations
LOAD_A - load into Reg_A particular bit from DATA
LOAD_B - load into Reg_B particular bit from DATA
DATA <7:0>
OUTs:
Seg <6:0> - seven-segment display (with active '0')
Anod <3:0> - bits for another 4 displays working similarly to Seg
LED <7:0> - bits for diodes' steering

2. steering block:
ins:
CLK, RST, EXEC, LOAD_A, LOAD_B
Exec is a rising edge that starts the counting sequence and all the data 
thrown at Exec while its working is being ignored.
outs:
random variable that, based on set logic, decides when to load data from 
DATA and when to shift what's loaded on registers


3. register_block
includes 2x 8-bit register, named REGISTER_A and REGISTER_B
outs: LED
Here i've also got some problems with creating proper logic for these 
registers; they're both shift registers and i know how to set it up, but 
I have no idea how to program that they send 1 bit of data starting from 
the youngest bit when EXEC is active.

4. calc_block
Here's another problem - out of the blue in the description of my task 
i've got info that this block executes logical operation based on F<2:0> 
(I've got necessary data to fill F with it) but it also says its the 
result of L_AB and i don't know whether i should take it as the result 
of shifting data between registers or not.

5. Router
It returns info to the register_block - I have no idea how to implement 
this in my project. The whole description goes like that: it takes 
signals A and B and the result of L_AB and sends to register_block 
signals New_A and New_B based on the selection of R<1:0>

6. Display
It's just a standard seven-seg display with a dynamic display for 
thousands, hundreds, tens and ones.

Summing up, I'm getting lost around while working on points 3 to 5.

Thanks in advance, I believe that just a bit of explanation for points 3 
to 5 and some kind of a block diagram presenting connections between 
particular blocks would be more than enough for me to finish that 
project.