One way to approach this is through consideration of the idea of "peak oil", i.e., the idea that at some point there will be a peak in oil production that will never again be reached. The reasoning behind this is a mixture of the finite nature of oil reserves and the economics of oil extraction. One important component of the peak oil concept, which also reflects a misconception within your question, is that we will never ever get the last drop. There will always be petroleum left behind in a reservoir because at some point the cost of extraction greatly exceeds the price to extract that oil. If you look through the linked wikipedia page, you'll see how this plays out when a new way to extract oil becomes available. Specifically, the original peak oil prediction suggested that oil production would peak sometime in the early 1970s and this basically held until about the mid 1990s (in this plot the red is the projected production based on the peak oil concept and the green is actual global production). So what happened in the 1990s that allows production to go back up? A few things, but primarily development of technologies that allowed us to start efficiently extracting petroleum from reservoirs that were previously non-viable (primarily directional/horizontal drilling coupled with hydraulic fracturing that allowed us to extract oil from "tight" reservoirs, but others as well). This highlights that it's hard to project out when we will actually effectively run out of oil because we fundamentally don't know the future in terms of development of new ways of extraction (and to a lesser extent the discovery of additional reservoirs, though both the rate of new finds and the general exploration process is a shadow of what it was in the mid 20th century).

The other important side is demand. Circling back to the beginning, oil companies are not non-profits, they only extract oil if it's economically viable (and profitable) to do so. If factors reduce demand (e.g., taxes on petroleum to reflect the huge environmental cost of continuing to burn oil/gas, decreasing prices of alternative energy sources, etc), demand for, and thus the price of, oil will drop below a point where it's economically viable to extract whatever is left in reservoirs. Analyses attempting to work in some of these ideas of changing patterns in demand and viable energy alternatives still consider the peak oil concept, with some projections now pointing to a peak in production in the mid 2030s (e.g., Delannoy et al., 2021). But again, a lot is riding on projecting out a variety of pretty hard to predict things (basically anytime one group of variables is "collective human behavior", projections are going to be a bit tricky).

The final point to consider is that if we consider some hypothetical where we really go for getting as much remaining petroleum as we possibly can and burn it all, even without considering the "what do we do now for energy" challenge, this would basically be a "let's shoot for a RCP 8.5 scenario", which would make for some pretty hellish conditions in the future, to put it mildly.