Why will Crude Oil run out? What can this lead to? What can we do?

-Crude Oil is Limited, and therefore is a Non-Renewable Resource -We can find New Reserves, but it'll simply Run Out soon -Finding Alternatives to replace what Crude Oil provides eg Oil is very Essential , especially Now as leaving it Later means we may be too Late -Conflict can be Established due to people Arguing about where Oil should be Used.[Example] Plastic Production or Literally No where?