Open .bas files only

[Jack]

@PhilOfPerth
simply put, .bi and .bm are basic include files
but since QB64 doesn't allow function/sub code before your main executable code but only declarations, you have the .bi that is included before your main code, the .bi only contains declarations
then you have the .bm file containing the functions/subs, so your program may look like this

'$include: 'some.bi'
your main code
'$include: 'some.bm'