I am drowning, would any one of us be so kind to throw me a lifesaver... in time :)

I am adventuring myself in deployment a .NET Core Worker Service app in Linux. Am trying to create a package for that.

[This article](https://medium.com/bluekiri/packaging-a-net-core-service-for-ubuntu-4f8e9202d1e5) seems to tackle exactly what I want to achieve.
Have followed it, but my `dpkg-buildpackage -b --no-sign` is failing, as far as I can tell in the install statement below:
`install -D -m 755 bin/Debug/netcoreapp3.1/linux-x64/publish/* /opt/myApp` (the install statement is part of my `rules` file created after running `dh_make` as instructed in the article)

My `rules` files:

```
#!/usr/bin/make -f
# See debhelper(7) (uncomment to enable)
# output every command that modifies files on the build system.
#export DH_VERBOSE = 1

# see FEATURE AREAS in dpkg-buildflags(1)
#export DEB_BUILD_MAINT_OPTIONS = hardening=+all

# see ENVIRONMENT in dpkg-buildflags(1)
# package maintainers to append CFLAGS
#export DEB_CFLAGS_MAINT_APPEND  = -Wall -pedantic
# package maintainers to append LDFLAGS
#export DEB_LDFLAGS_MAINT_APPEND = -Wl,--as-needed

%:
    dh $@ --with=systemd

override_dh_auto_build:
    dotnet publish -r linux-x64 --self-contained true -p:PublishTrimmed=true

override_dh_auto_install:
    # install application
    mkdir -p /home/myUserName/myApp
    echo 'Log Message 1'
    install -D -m 755 bin/Debug/netcoreapp3.1/linux-x64/publish/* /home/myUserName/myApp
    echo 'Log Message 2'
    rm /home/myUserName/myApp/*.pdb #delete pdb

    # install debug symbols
    mkdir -p /home/myUserName/debug/myApp
    install -D -m 644 bin/Debug/netcoreapp3.1/linux-x64/publish/*.pdb /home/myUserName/debug/myApp
    dotnet-symbol --symbols bin/Debug/netcoreapp3.1/linux-x64/publish/ -o  /home/myUserName/debug/myApp
    # auto-install disabled

override_dh_shlibdeps:
    # shilbdeps disabled

override_dh_strip:
    # strip disabled

# dh_make generated override targets
# This is example for Cmake (See https://bugs.debian.org/641051 )
#override_dh_auto_configure:
#   dh_auto_configure -- #  -DCMAKE_LIBRARY_PATH=$(DEB_HOST_MULTIARCH)

```

If I run it separately, adding the verbose flag (-v), I do not see any error messages (tried `| grep -i error`, nothing).
I am a beginner in Linux, I learned that echoing `$?` gives me the last statement exit code (for that matter, running an ls and echoing $? returns 0, running the install statement above and echoing $? returns 1).

Running `errno 1` gives `EPERM 1 Operation not permitted`

I thought perhaps the problem is in writing to /opt. Changed the destination folder to something within /home, still get the same results.

How do I proceed from here ? How can I know what is going wrong with this install statement ? Somewhere I read that the package must be installed. I run `dpkg-deb -I myApp`, but it returns `error: failed to read archive 'myApp': No such file or directory`, which I believe indicates the package is not installed.

Please be so kind and save a life !