You can see right here.
https://www.livescience.com/new-coronavirus-compare-with-flu.html
So influenza's death rate is 0.1%, whereas they estimated COVID-19's death rate at 2.3% (WHO upgraded the number to >3).
The other number to look at is R0, which is how easily the virus spreads. The flu R0 is calculated to be 1.3, whereas they have it at between 2-3 for COVID-19. So it appears to spread more quickly.
Now, let's say the death rate settles at 0.5%. That's still 5 times higher than Influenza's death rate.
The other issue is vaccine. At least with the flu, we have a vaccine, although it isn't 100% effective, but it is known to reduce the symptoms. Here, we don't have any vaccines.