Dark Energy, from theory to data

Cosmology is advancing thanks to contributions from theory, data, and methods that link them. I will discuss recent results I have been working on, which touch these three aspects. I will in particular discuss: a) coupled dark energy and the H0 tension; b) weak lensing statistics as a tool to distinguish different theoretical models; c) forecasts for the Euclid satellite space mission, whose launch is expected in 2022.