The Usual Guidelines
For each adult, standard-sized hen you need:
4 square feet in the coop,
10 square feet in the run,
1 linear foot of roost,
1/4 of a nest box,
And 1 square foot of permanent, 24/7/365 ventilation, preferably located over the birds' heads when they're sitting on the roost.
Other's have explained why the space guidelines are important -- and there are also times when you'll want more space rather than less (see this thread for a discussion:
https://www.backyardchickens.com/th...ave-more-than-the-minimums-for-space.1462570/). And here is an excellent article about why these are guidelines rather than rules:
https://www.backyardchickens.com/articles/how-much-room-do-chickens-need.66180/
Here is the math worked out and converted to meters for a flock of 10, standard-sized hens:
40 square feet -- 3.7 square meters -- in the coop.
100 square feet -- 9.3 square meters -- in the run.
10 linear feet -- 3 linear meters -- of roost.
3 nest boxes.
and 10 square feet -- .93 square meters -- ventilation, preferably located over the birds feet when sitting on the roost.
I wish I could be more helpful beyond translating the numbers from English to metric but I don't have any idea what standard measurements are for lumber in your country (in the USA it comes in multiples of 4 feet), so I can't make suggestions about what size would be easiest for an inexperienced handyman to build.
In the US I'd recommend a 6-foot by 8-foot, walk-in coop -- which would be a little larger than the minimums but would be easier to build with fewer cuts and less waste -- and an 8-foot by 12-foot run (just slightly smaller than recommended but within range), or an 8-foot by 16-foot run (generously-large). The important thing is to minimize cuts and waste.
What we usually recommend to people with minimal building skills are:
A. Buy a wooden or metal shed the desired size and convert it,
B. Buy a chainlink dog kennel the desired size and convert it,
C. Make a Hoop Coop.
https://www.backyardchickens.com/se...ries][0]=19&c[child_categories]=1&o=relevance
Each has it's pros and cons.
