Time format in Excel by default is "HH:MM:SS", but they can be formatted into different styles.
– How to Enter a Number
– How to Enter a Fraction
– How to Enter a Date
– How to Enter Text Content
1. To Enter a Time
For example, to enter a time of "4:20:15":
Step 1: Select a cell and type the hour "4" from the keyboard

Step 2: Type the time separator: ":" (colon)

Step 3: Enter the minute by type "20"

Step 4: Type another colon separator

Step 5: Enter Second (e.g., 15)

Step 6: You can format to a different style, please check how to format time into different styles.
The time format in the formula bar will not changed even you changed to a different format in the cell.

2. To Enter Current Time
To enter current time, you can use:
– Excel function of "=NOW()", or
– Excel shortcut of "Ctrl+Shift+:" (colon).
"=NOW()" will have us the time with today's date while the shortcut will have us only the time.