Just press space to make the dino jump, or on mobile activate mobile mode by pressing the green button at the top right, then click the big red button the appeared to jump. If you want to turn off mobile mode, press the small red button.
-- UPDATE LOG -- 9/9/2021: The mobile update is out! Press the green button at the top of the screen to activate it, the small red button to deactivate it, and then the big red button to jump. The speed change update also came out today! Every minute, the cacti appear 0.05 seconds faster than before, until it reaches a set of cacti every three seconds. FUTURE UPDATES: I plan to add a title screen, where you can change settings, such as how fast the cactus speed changes are, how much they are, and the default speed for cacti.