The involvement of the common man to fight climate change

There are numerous fossil fuel (or) petroleum industries in the modern world. And each industry is linked to the citizen by some means, either a person has invested in a fossil fuel producing company (E.g. Shell) through shares, or it might be his workplace, etc. These industries are working and successfully running thanks to us. How feasible would it be for a person to cut out all his expenditure/time from those industries after finding out whether his resources/money are being directed to run that company?