Liberals (and neoliberals) want everything controlled by markets. The government should butt out and collect no more taxes than is reasonably needed to set and enforce the market rules. Everything else should be private. Not too different from libertarians except that they have more common sense.
Leftists want the government to have an opinion and directly act and spend money in order to achieve specific outcomes. If there are many homeless, don't try to influence the market to increase supply or drop price, just directly go and build houses. If we need clean energy, don't dick about with carbon credits and incentives, just go and hire some engineers and build wind turbines.
Liberals and leftists are opposites not synonyms.