Ok and if I upgrade to the complete vantage pro 2 weather station (without console)? So I mean is the ADC included in the white solar box?
Yes, the ISS circuit board (inside your 'white box') does have a low-power microcontroller analogous to Pico which will have an A2D interface. But this doesn't mean that you can easily access the data. VP2 sensor assemblies come in two types - wireless (868/900MHz) and cabled. Wireless obviously needs a suitable receiver, which is one of the roles that the console provides. Cabled is potentially more accessible since it passes data via an RS422/485 interface but only in the form of coded
binary data packets (that aren't documented - officially at least). So you could in theory fit an RS485 interface board (eg a HAT) to a Pi but there would be a lot of work in working out how to decode the data packets and how to program for that.
So that I connect the white box to the Raspberry and read out the data using ready-made software. (https://github.com/ardexa/davis-weather-station)
I think this sort of software assumes that you're going to have a console and then eg a USB logger which provides a data stream that's a lot easier to work with. If you have a console/logger and a Pi then there's a lot of other readymade Pi-compatible software such as CumulusMX that will provide all the data functionality that you might ever need.
More generally, there's a whole spectrum of solutions for interfacing Davis sensors to a Pi ranging from bare sensors interfacing direct to a Pi via eg an A2D converter where necessary or a microcontroller with build-in A2D like Pico right through to the standard solution of VP2 sensor assembly + console + logger where you can use powerful freeware or commercial software. But if you want to use a simple/cheap solution like bare sensors and a Pi then there's a lot of programming work that you'll need to do. Many people have trodden this path and there's a lot of information out there on the web, but don't assume that bare sensors can provide a a single easy-to-use data stream in eg text format - they can't! A very interesting and worthwhile project to use eg bare sensors + A2D + Pi, but don't underestimate the development work involved.