VBA code to replace "1" with "7:00/ 15:30"

[GLV]

As i said, i am newbie. Barely know a thing or two about VBA.
I attached the spreadsheet in which i need this replacement to take place.
Basically, when i type 1 and press enter, i need it to automatically change into "7:00/ 15:30".
Many thanks !

Welcome to the forum,

What version of Excel do you use?

Also a little confused, in the title you state: "VBA Code to replace"
But then in the main text you state: "But with no macros."

Microsoft® Excel® for Microsoft 365 MSO (Version 2302 Build 16.0.16130.20332) 64-bit