You will have to write a text parsing program. I don't know why you would want to do this, but it could be done. It would take a lot of coding to do it.
You would need to load the text file either with a lot of read commands or make a memblock from a file. I would use the later. Then you would have to parse thru all the data checking for syntax and errors along the way. Take all the data collected and store it as an array or arrays. Compare all that info with a known data set (probably data statements or another file) and then execute that command or commands with the parameters given.
Very Generic Example:
line$(1)="make object sphere"
objectnum(1)=1
size(1)=50
for l = 1 to whatever
if line$(i)=known$(i) then make object sphere objectnum(i),size(i)
next l
I'm not about to write it for you. I'll help with certain problem issues, but basically you're on your own.