Hello guys,
i have recently tried to install a set of icons which requires clang (a compiler) along with icons-in-terminal (which is icon printing utility) from Github. but I never really understood the instruction they provide. here is the link of github projects:

https://github.com/sebastiencs/ls-icons

dependency:
clang
https://github.com/sebastiencs/icons...l#integrations

Can you please tell me what is the instruction dictates??

once installed you can run these instruction :: (but what does it mean???)

$ ./bootstrap
$ export CFLAGS=-DNO_TRUE_COLOURS=1 # Execute this line _only_ if your terminal doesn't support true colours
$ export CC=clang CXX=clang++
$ ./configure --prefix=/opt/coreutils
$ make
$ make install
$ /opt/coreutils/bin/ls

bootstrap is this script. It's part of Gnulib. It makes some preparatory work for software that is being built from a git snapshot (contrast this with software released as a tarball), e.g. in this case it fetches the latest gnulib. Most of the time such a script would also call autoreconf or something similar. Upstream developers usually would call this when preparing a tarball for release.

Incidentally, the incantation "./" at the start of a cmd means you have to be in the dir where the cmd/script you want to run actually lives.
IOW,
means ensure you are in the dir where bootstrap lives, then run the cmd .
HTH