Why was the loop for i not taken into consideration while calculating the complexity? Im confused

# Why was the loop for i not taken into consideration while calculating the complex

first loop runs = N/2 times

second loop runs = N times

now according to the time complexity we reach N/2+N

Now if N tends to infinity then N/2 is very small compared to N. Hence can be neglected.

O(N) is the final answer.