There's not much to explain about this final chapter of the Left Behind DLC, so just get stuck in and enjoy the conclusion!
Escape from Liberty Gardens
Start this final chapter by helping Riley open up the garage door. Once you've done so, take a left and then take the shopping trolley and use it to keep the gate open. Keep following Riley as closely as possible, fending off any infected that attack either you or her. When the fighting finishes, make sure you keep the pace up.
As for the rest of the chapter, it's pretty much a cut-scene that runs through the end of the DLC.
Head back to the first page for the rest of our The Last of Us Remastered guide.