The word “happy” has a tense “ee” sound at the end. This common word ending, spelled -y, is typically pronounced “ee”. The tense “ee” sound is a long sound, made with your tongue high and your lips smiling. The sides of the tongue are pressed against the roof of the mouth.
The “h” sound is made by opening your mouth and exhaling a huff of air from the lungs. To make this sound, pretend you are trying to fog up your glasses to clean them. If you’re a Russian speaker, make this sound a bit softer. The American “h” doesn’t have an audible friction sound.
The “o” sound in American English is long and has a slight “w” sound at the end. To sound like a native speaker, double this vowel sound and really round your lips at the end.