I assume you're talking the Spanish Flu?
A conservative estimate is that about 17 million people died worldwide (some estimates are over 50 million) and the world population was about 25% what it is today. About 6 million people have died from COVID, so adjusting for population and using conservative estimates about 11x more people died from the Spanish Flu.
IN the US about 675,000 died and the population was about 1/3 that it is today, so adjusting for that about 2x the people died from Spanish Flu.
Here's the kicker though.....95% of the deaths were in people under 65 (and I realize people didn't live as long then) and almost half the deaths were in people 20-40. It mostly killed young adults. An entirely different situation. And yet, when most history books talk about that period in history, in particular the time between 1900 and World War II, I'd say the Great Depression gets 50x more mentions than the Spanish Flu.
So yeah, not comparable at all IMO. I don't think we'd have noticed much at all if a higher than usual number of mostly all elderly people were getting sick and passing away a year or a few years earlier than anticipated.
My grandfather was born in 1910. He never mentioned the Spanish Flu. Most people of his generation were concerned about World Wars and the Great Depression. His dad died from Pneumonia in 1930, well after the Spanish Flu.