Your frustration is due to not understanding the difference between Linux
and Windows. They have a different history and you cannot apply what you
know about one OS to the other. It works in reverse as well.

Hidden files and folders all begin with a dot. You can find them in your
file manager by using a hot key (it will be Ctrl+H for Ubuntu's Nautilus
file manager and Alt+. for Dolphin used in KDE). Or you can go to the menu
under View, Show Hidden Files.

As for executables. There is either none or all depending on how you look
at it. Unlike Windows you do not need a file suffix at all in most cases.
If a jpg file does not end in .jpg, Linux still knows what it is. Windows
will not. Linux looks at the contents of the file. A .exe suffix would be
useless and extraneous. Files become executable by changing the file
properties. If you right click on the file then it can become executable by
ticking the box on the Permissions tab to say Execute. If it is not meant
to execute ticking the box will be of no help.

You will also see that is can be different for different users and levels.
In some cases this will have to be done as root (admin). In those cases you
will have to open the file manager from a terminal using sudo. Open the
Terminal by typing term.. (it will pop up after a few letters) in the Dash
and it will come up. Type or copy and paste this: sudo nautilus and it will
prompt you for your password. Do not close the terminal till you are done.
Nautilus will open as root and you will have admin privileges and can
browse the root file system and make system changes. This is dangerous for
the unknowledgeable so that is why you need to give your password. Note the
home folder will not be your own, but root's so you will have to click on
home in the ribbon on the left and navigate to the file.

You have also learned another major difference between Linux and Windows.
Linux makes you jump through more hoops, but the trade-off is that you have
more power and security. This is for your protection and convenience once
you get the hang of it.

Linux was built new from the ground up and did not try to copy Windows. So
you will have to re-learn things to avoid future frustrations.

BTW, you seldom need to install a binary file. All installation that most
users will ever need is done by the package manager. One comes with each
distro. Ubuntu use the apt package management system and on the front end
it uses Software Center, but I prefer either issuing commands in the
terminal or using Synaptic (which needs to be installed because it is no
longer a default application). You also do not need to search the internet
for files to install. The come in app stores called repositories and they
are managed and maintained to be virus and malware free. The system used by
Android and the iPad/phone are copied from Linux so if you understand how
to install on them you will quickly pick up how Linux has been doing it for
at least a dozen years graphically and since the beginning from the
commandline.