Voting matters, but unfortunately it appears to be an incredibly sub-optimal solution for dealing with climate change for the following reasons:
Just because you can vote, doesn’t mean that the option you need is even on the menu. It often isn’t.
Through hard work you can get the option on the menu, but that doesn’t mean your politician won’t do “deals” after they are in power.
Lobbyists get access to politicians 24/7 and have a lot of influence, you have one vote every 4 years;
Even if politicians do what you want, it is unlikely that your country by itself will make a difference, this is a global problem.
Meanwhile we are all fucked. It is likely too late already for preventing severe climate change. Our only hope now is geoengineering. The USA and EU are already considering blocking the sun.
The people who (rightly) have a sense of urgency about this are taking more radical action. They are blocking roads and throwing soup at famous paintings. These are desperate acts that seem rational in the face of the horror that we should strive to avoid, but the majority opinion of our species seems to be that these people are “too radical” and that common folks just trying to get by should not be inconvenienced, and that these radical eco-terrorists should be thrown in a cage.
To be honest, I’m not sure that our species deserves to survive.