Bring water and rice to a boil in a saucepan. Reduce heat to medium-low, cover, and simmer until the rice is tender and the liquid has been absorbed, 20 to 25 minutes.
Heat sesame oil in a large skillet over medium heat; cook and stir collard greens, garlic, and red pepper flakes in the hot oil until collard greens are wilted and tender, about 10 minutes.
Mix almonds, lemon juice, soy sauce, and ginger into collard green mixture; simmer until liquid evaporates, about 5 minutes.