Hello Beatriz,
There are two ways that a carbon footprint is typically discussed in the industry, and each has their own answer.
1: A carbon footprint is just a number, the total impact on global warming potential for your product system. It represents the GWP impact in your designated system boundary. If this is the carbon footprint you want, then simply check the impact analysis tab when you have calculated the product system, and take out the climate change value.
2: A carbon footprint in accordance with e.g. ISO 14067. If you need to subdivide your results onto climate change subcategories to meet a standardized reporting format, you will find it more difficult to do, using ReCiPe. I usually use the EF 3.1 LCIA method for subdivision into carbon categories.
I hope i answered your question, if not comment back.
Good luck