Help with basic heating control

Dear All,

my first post here since I am quite new in the impressive world of automation based on Node Red. I am now experiencing my first issues and I hope some of you guys can show me the right way. Please have a look at the scatch as attached which should serve as MWE for my heating control plans (the actual project is more comlex). So the basic idea is to trigger individual flows (Auto/Boost/Off) via dashboard buttons. In a way that the pushed button gets a different colour (say green) if compared to the non active buttons (say gray). However, in the first instance I have no idea how to individually trigger the flows. Any help would be aprreciated. Thanks!!heating control