The Bywater BASIC Interpreter (bwBASIC) implements a large superset of the ANSI Standard for Minimal BASIC (X3.60-1978) and a significant subset of the ANSI Standard for Full BASIC (X3.113-1987) in C.

https://sourceforge.net/projects/bwbasic/

apt install bwbasic

/usr/share/doc/bwbasic/README.gz

/usr/share/doc/bwbasic/examples

save "/home/user/file.bas"

load "/home/user/file.bas"

https://packages.debian.org/search?keywords=bwbasic