Self-heating composite foam fracturing fluid capable of being controlled in real time and on-site construction method

The invention relates to a self-heating composite foam fracturing fluid capable of being controlled in real time and an on-site construction method. The composite foam fracturing fluid comprises the following components in percentage by weight: 87.9-92.97% of base fluid, 6-10% of catalytic fluid, 1.0-1.8% of cross-linking fluid and 0.03-0.3% of gel breaker, wherein the base fluid is prepared from a composite thickening agent, a gas heat agent, a foaming agent, an acid stabilizer and liquid preparation water; the catalytic liquid consists of acid, a scale inhibitor and water, and is used when being prepared; the cross-linking liquid comprises a surfactant and a cross-linking agent. The on-site construction method comprises the following steps: respectively preparing a base solution and a catalytic solution according to a proportion before construction, sucking the base solution by a fracturing blender truck during construction, respectively adding a crosslinking solution and a gel breaker by a liquid adding pu