Richard,
MSP does not know that you are laying bricks or pouring concrete or shooting pigeons or whatever. There is nowhere in it (with the possible exception of "% Physical Complete which does not get used to calculate anything until later, maybe, at EV calculation) to say that you have laid 300 bricks out of 1000 bricks.
There is nothing to stop you using spare (number) fields to note the number of bricks (or m3 of concrete whatever) and the total planned bricks and then calculating with a formula the % of bricks laid in another field.
"% anything" is always best left to be a calculated number from raw data rather than raw data.
If someone (the junior engineer) tells me that "the roof is 50% complete" I want to know which numerator and denominator they used to calculate that, especially if it is a mixture of framing, tiling, guttering etc.
"the roof is 50% complete" is a very ambiguous phrase.
It could mean:
"% of m2 actually done compared to total m2 planned"
or "% of actual hours compared to total budget hours/as planned hours/estimated hours"
or "% of actual Cost compared to total budget cost/as planned cost/estimated cost".
One very popular calculation is done by eyeballing the work in progress, guessing at "% progress" (whatever that means without a numerator or denominator) and calculating a figure called "Earned Hours" by "Earned Hours" = "% progess" x Total budget Hours for the Task. And this is then used as a proxy for EV.
I don’t like it. I don’t recommend it. I don’t know why it is so popular but it is. I don’t see why it is necessary or useful or why it is used instead of Cost or why Cost isn’t used as well or instead of. I’ve got issues with it which I won’t go into here.
Similarly "% progress = such-and-such" is ambiguous, verging on meaningless and downright dangerous, if we don’t know what is being measured as a % of what.
"% Complete" is % of Duration elapsed, as a percent of total estimated duration for the Task.
% Complete is best left to be calculated by MSP rather than being put in by you.
It is a mistake to see 300 bricks out of 1000 laid and type in 30 at % Complete, even if it is also true that 30% of the planned Duration has elapsed, and therefore the % Complete does equal 30%.
When you have set a baseline set (Tools, Tracking, Baseline), and the Tracking Gantt View, with the Tracking Table and the Tracking Toolbar all displayed you can select the Task and upate it.
Before starting to update, make sure you have nominated the Status Date in Tools, Project Information and by right clicking in the Gantt Chart area, format the gridlines with a nice vertical red line straight down the Status Date.
Do not show progress Lines because they are a useless source of confusion.
The first thing to put in is the Actual Start Date.
However, if you know that it started on the scheduled start date (The ES for CPM and scheduling forward) you can skip this step because the Actual Start Date will be assumed to be the ES when you do the next step, but it is important to put in the Actual Start Date if it is different from the ES.
Next, with the Task still selected, and assuming that bricklaying has proceeded continuously since the start (not a bad assumption), click the "update as scheduled" button on the Tracking Toolbar. If it started and stopped this must be accounted for and can be, but let’s not just yet.
Try this with just one Task "Lay 1000 bricks" with Duration = 10 days, resource = bricklayer WORK $50/hour, + resource = 1000 bricks MATERIAL $1000 cost-per-use.
Then run through the update exercise described above.
Then try variations.
What happens if the Status Date is at end of Day 6, you hope to see 600 Bricks laid but only 300 are?
How do you put this in MSP (or do you?) and since our original duration estimate was way off and should have been total 20 days because observed production is half of what was estimated/hoped for, how and when do you re-estimate the Remaining Duration and when you do, what happens to that Task’s Successors?
Many people do not like to convert bricks or concrete or pigeons to Cost but it is the only way to reduce them all to common dollars in order to do EV which needs BCWS, BCWP, ACWP.
The C stands for Cost, and that’s dollars, not bricks/concrete/pigeons.
It doesn’t stand for (man) Hours of Work either, unless all hours cost the same dollars.

peace to all for xmas

Rather than me assuming what I think you mean, can you define further what you mean by these terms?