The Excel NOW function returns the current date and time, updated continuously when a worksheet is changed or opened. The NOW function takes no arguments. You can format the value returned by NOW as a date, or as a date with time by applying a number format.
Purpose:
Get the current date and time
Return value:
A number representing the current date and time in Excel.
Syntax: =NOW ()

Examples:
The examples below show how the NOW function can be used in various ways:
=NOW()
// current date and time
=NOW()-7
// last week same time
=NOW()+7
// next week same time
=NOW()+90
// 90 days from now
=MROUND(NOW()+90,"1:00")
// 90 days from now to nearest hour
=EDATE(NOW(),3)
// 3 months from now, time removed
=EDATE(NOW(),12)
// 12 months from now, time removed
=EOMONTH(NOW(),-1)+1
// first day of current month
=EDATE(NOW(),6)+MOD(NOW(),6)
// 6 months from now, time preserved
Static date and time:
If you need a static date and time that won’t change, you can use the following shortcuts:
Insert current date – Control + ; -> the cell will have current date like 25-07-2022.
Insert current time – Control + Shift + ; -> the cell will have current time like 16:37.
To enter both values in a single cell — Control + ; leave a space then Control + Shift + ;
output: 25-07-2022 16:37
Instead of “space” any other character can also be used.