It happens to you, to me and to every UNIX user since the 70s. Your system is (or should be) full of docs and tools to get help. One thing that I noted over the years, when we have new people at work, is that they don't known how to get help from programs or they don't known how to get help from their systems and when they struggle with anything, doesn't matter how basic, they go to the web for help. I always show them this: apropos
man
help
What was that command to compress files?
apropos compress
Oh! it was gzip
What was that command to do whatever with the GRUB?
apropos grub
Oh yeah! update-grub
What about that command to download files?
apropos download
Oh! it's wget
The next tip should be learn how to use and navigate in the man
pages, man have it's own man page;
man man
There are different sections, section 1 is the default, you don't need to specify, so you can just;
man bash
But if you want to get help from configuration files you should type;
man 5 sysctl.conf
Also, almost every program have a built in help compiled with the program code, you usually call it with --help or -h, sometimes just help and other times just call the program without parameters and it should print it.
Other people already suggest the cheat sheets, very useful especially for programas like vim or emacs, some of them come like a template to create a cube, so you print it and then craft it (like an origami) and you can have it in your physical desktop.
Last thing; be patience, your are in the rigth path, there's always more than one way to do things, you just need to find your own way.