Autoremove tries to remove needed packages in Ubuntu. How to fix?

Question

Nginx

Hello,
Ubuntu server has NGINX + PHP-FPM + MariaDB installed.
when installing and updating packages, the system constantly reminds you that there are unnecessary packages that should be removed:

The following packages were automatically installed and are no longer required:
  aspell aspell-en dbconfig-common dbconfig-mysql dictionaries-common emacsen-common fontconfig-config fonts-dejavu-core gcc gcc-5 javascript-common libapache2-mod-authnz-external libapache2-mod-rpaf libapache2-mpm-itk libasan2
  libaspell15 libatomic1 libc-client2007e libc-dev-bin libc6-dev libcc1-0 libcilkrts5 libfontconfig1 libgcc-5-dev libgd3 libgomp1 libitm1 libjbig0 libjpeg-turbo8 libjpeg8 libjs-jquery libjs-sphinxdoc libjs-underscore liblsan0
  libmcrypt4 libmpx0 libquadmath0 libtiff5 libtsan0 libubsan0 libvarnishapi1 libvpx3 libxpm4 linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-headers-4.4.0-75 linux-headers-4.4.0-75-generic linux-headers-4.4.0-78
  linux-headers-4.4.0-78-generic linux-headers-4.4.0-79 linux-headers-4.4.0-79-generic linux-headers-4.4.0-81 linux-headers-4.4.0-81-generic linux-headers-4.4.0-87 linux-headers-4.4.0-87-generic linux-headers-4.4.0-89
  linux-headers-4.4.0-89-generic linux-headers-4.4.0-91 linux-headers-4.4.0-91-generic linux-image-4.4.0-21-generic linux-image-4.4.0-75-generic linux-image-4.4.0-78-generic linux-image-4.4.0-79-generic linux-image-4.4.0-81-generic
  linux-image-4.4.0-87-generic linux-image-4.4.0-89-generic linux-image-4.4.0-91-generic linux-image-extra-4.4.0-21-generic linux-image-extra-4.4.0-75-generic linux-image-extra-4.4.0-78-generic linux-image-extra-4.4.0-79-generic
  linux-image-extra-4.4.0-81-generic linux-image-extra-4.4.0-87-generic linux-image-extra-4.4.0-89-generic linux-image-extra-4.4.0-91-generic linux-libc-dev manpages-dev mlock php-auth php-auth-sasl php-crypt-chap php-db php-gd
  php-gettext php-imap php-intl php-ldap php-log php-mail php-mail-mime php-mail-mimedecode php-mbstring php-mcrypt php-mdb2 php-mysql php-net-ldap2 php-net-ldap3 php-net-sieve php-net-smtp php-net-socket php-phpseclib php-pspell
  php-soap php-tcpdf php7.0-gd php7.0-imap php7.0-intl php7.0-ldap php7.0-mbstring php7.0-mcrypt php7.0-mysql php7.0-pspell php7.0-soap pwauth roundcube-mysql snap-confine
Use 'apt autoremove' to remove them.

Although in fact many of these packages are needed, for example, PHP 7 modules like GD, mysql, mbstring, etc.
What needs to be done so that the system understands that these packages cannot be removed?

Answer 1

If autoremove offers to remove the package automatically, then it was installed by dependencies, and now no one else depends on it. Or somehow the flags about manually installing these packages have been lost.
A package can be flagged "manually installed" via apt-mark so it will not be removed via autoremove.
apt-mark manual имя_пакета

Answer 2

Install packages for which they are intended

Answer 3

Is it by chance that apt-get upgrade or apt-get dist-upgrade has not been done before? If so, then the current version is 4.4.0-93, so autoremove tries to remove older versions.