Date format changes to numbers in simple formula

After scouring this forum I wasn't able to find the answer I was looking for.
To simplify my formula lets say cell A1 is a date:
12/31/2023
Cell B1 is that date plus one day:
=A1+1
returns me: 01-Jan
Cell C1 is that date plus five days:
=A1+5
returns me: 05-Jan
In cell D1 I have:
="From "&B1&" to "&C1
I want D1 to read a from and to date like this:
From 01-Jan to 05-Jan
But I get this...
From 45292 to 45296
Formatting the cell to date format yields no result... Any advice? Thanks!