Can anyone make a list with the zones that is
impossible to plant figs outside?

Also what about if you had this trees in pots and brought
them inside at winter, would those trees produce any fig

Sorry for the stupid question, I'm totally clueless when it comes to gardening

Most of us have trees in pots and bring them in for the winter.  I know someone in zone 7 who leaves his trees out protected in the winter and they do fine.

There are plenty of inground trees in zone 6a in my area. They are either wrapped or buried.
You should have no problem planting a tree inground. Just make sure you get one of the more cold hardy varieties.
I'd still keep it in a pot for the first year or two.

There are also a few trees that grow unprotected. Depending on the winter they may die back to the ground.

There's all kinds of information out "there" on this subject, not sure if you are just curious about where figs can be successfully grown, or more in just your Zone?

Here's one bit of info

Growing figs
The fig tree is a handsome ornamental, with silvery bark and very large leaves. The branches often age with a twisted, sculptured look. Unfortunately, most figs are not hardy above Zone 6. In Zones 6 and 7 figs are root hardy, but since the trunk dies each year they form a bush instead of a tree. The variety Brown Turkey may overwinter outside as far as Zone 5, if it is in a protected place or on the south side of a building.

Figs grown in containers need one that is large and sturdy that drains well. It may be easier to move if it is on wheels. Fill the container with a high-quality potting soil that has slow-release fertilizer added. The fertilizer will need to be renewed each year, and the fig should be repotted in fresh soil every two to three years. Keep the container well-watered so the plant doesn't wilt, but never let it become too soggy. Containers that sit on pavement or are hit directly by the sun may need to be shaded so the roots of the fig don't become too hot. Figs in containers should be dwarf varieties.

Source: http://www.life123.com/home-garden/trees-shrubs/fruit-trees/yes-you-can-grow-figs.shtml

And this
Container culture: Because figs are tricky to grow in the ground where temperatures drop below 10°F, if you live north of Zone 7 it makes sense to grow your figs in containers. Use a large container (such as the patio planters nurseries sell for patio fruit trees), preferably plastic to control the weight. Use regular organic potting soil and plant figs at the height they grew at the nursery, top-dressing the container with compost if you have it. Water when the soil is dry an inch below the surface; if you let containers dry out completely, the figs may lose their leaves. (Leaves will regrow, but it stresses the plant and lessens fruit production.) Set pots in a sunny part of the patio, deck, or yard. You can use foliar sprays or water with liquid seaweed (kelp) or compost or manure tea monthly to give plants a boost.
Source: http://www.organicgardening.com/learn-and-grow/fig-trees-growing-guide

I was talking about other colder zones, what is the coldest
that the fig will be able to produce figs?

There are some members here growing in zone 4 (Canadian)  I don't know if they have grown them before or if this is the first year though.