The "Loaded from floppy" part was compiled for a different base offset than the one it was loaded into, you need to recalculate its address
You could also use ORG 7C00h
and spare yourself the jump, the difference being your segments will be 0 instead of 07C0h
You can either calculate the new offset as [L1-prog] or you can reorder your code:
jmp 1000h:000Ah ; Jump to the program
....
L1 db "0123456789" ; my string
prog:
mov ah, 0x0E
...
mov al, cs:[bx]
I don't have an assembler to test but you get the idea - remove the need for a floating address, put it in the beginning
I roughly estimate your actual offset in segment 1000H to be around 32-ish, that's where your translated L1 will roughly be. Instead your L1 is calculated compile time to be about-ish 550, so you're actually trying to load something from the second sector you read. Do you have some blank characters or zeroes in the beginning of the second loaded sector?