build-essential is not installed by default in 18.04. How to install network drivers offline?

We have a serious problem with new installations on laptops that have only a wireless network device requiring some network drivers, like bcmwl-kernel-source.

Many laptops don't have an Ethenet port nowadays.

There is no build-essential in a default installation. So we can't install a dkms module or build anything from source.

The only way is to manually download very many packages required to install build-essential and install them manually using dpkg.

Is there any other way that an ordinary user can go with?

This question arose from this question.

I suggested to install xenial that has build-essential by default.

If there is no other Ubuntu installation available, suggesting something like apt-offline doesn't seem to be good enough.

It looks like all the required packages are provided on the installation media (pool directory). If anyone could suggest a script or any other simple way to download and install them all, it would be a great answer.

Nobody answered the question, so I'll try to post my suggestions that are not perfect.

One comparatively easy way to solve this problem is to connect temporarily to the internet using an Android phone or some other device. Then it is possible to install the driver a normal way.

Another way is to install dkms from an Ubuntu installation media. All required dependencies are there in pool directory. If you download all deb packages from there to Ubuntu Home directory, it will be possible to install all packages by sudo dpkg -i *.deb.

There must be a way to connect the Ubuntu installation media as a repo and install dkms using apt install. But I don't know how to do it.