When you want to use the superlative in Hebrew (the most, the biggest, etc.), you have two options.
The most common, colloquial way is to use the word הכי before the adjective.
For example:
זה השניצל הכי טעים שאכלתי אי פעם.
This is the tastiest (most tasty) schnitzel I have ever eaten.
The more formal way, often found in literature or news, is to use the word ביותר – this time after the adjective.
For example:
זוהי הבעיה הדחופה ביותר.
This is the most urgent problem.
