Where in Europe can we stay warm and nice in Europe ?
What do you mean by "warm"? Different people have different ideas.
As you are asking on the Opio forum can I answer for the Cote d'azur in which region this small town is? In the winter on the Mediterranean coast it is often warm and sunny during the day and cold ( but not frosty) at night. The locals describe the air as like 'champagne'. The climate here is extremely altitude sensitive - within a few kilometers of the coast the altitude rises dramtically so that e.g frost is not uncommon at Tourettes sur Loup in November and snow and skiing resorts can be found within an hour or two of the coast. Opio is locally considered to have quite a humid climate. Rain is more a common problem than cold in the winter.
About the only place in Europe where you can be fairly sure of warm weather in winter is Southern Spain. Can be fairly warm in Nice but it can also be around 5C at midday.