To know more about a command, check for more options and maybe some examples how to use it, you need to read the manual of the specified command. To access the man page of particular command is easy, just do the line below.
Let say I wanna access curl man page.
Or you can search for a keyword from all man pages you have.
But, this is not only what you can do. While you are in man, you can trigger search by specified a keyword. Man provides efficient browsing like in vim, you can bookmark a point and jump back to that point later, and a lots more.
With arrow key and PgUp and PgDn, you can navigate the man page easily, pressing g lead you to the first line of the page and pressing shift G brings you to the last line.
If you are vim user, the search act exactly the same in man. Press / follow by keyword. To jump to next point of keyword, press n, to jump back previous search point press shift N.
To mark down a location, press m follow by a letter, for example
To jump back to the marking point, press ‘ follow by the specified letter.
There are a lots of more function man can provide you, press h for help.