What is the greatest amount of time will the algo take depending on the number of inputs BIG ‘O’ notation

Where ‘n’ is the number of O(n²) O(n log n) O(n) Linear Search O(log n) Binary Search

What does the Log base actually do!?

O - this is the upper limit of the algorithm time. - The algo would not take more than this amount of time.

Omega - Given the any number of input, what is the fewest number of steps the algo might take.