• https://github.com/neovim/nvim-lspconfig/wiki/Comparison-to-other-LSP-ecosystems-(CoC,-vim-lsp,-etc.)

Practical vim tips and trick for all level

:echo @% def/my.txt directory/name of file (relative to the current working directory of /abc)
:echo expand('%:t') my.txt name of file ('tail')
:echo expand('%:p') /abc/def/my.txt full path
:echo expand('%:p:h') /abc/def directory containing file ('head')
:echo expand('%:p:h:t') def First get the full path with :p (/abc/def/my.txt), then get the head of that with :h (/abc/def), then get the tail of that with :t (def)
:echo expand('%:r') def/my name of file less one extension ('root')
:echo expand('%:e') txt name of file's extension ('extension')

:set et|retab

https://github.com/tpope/vim-unimpaired/blob/master/doc/unimpaired.txt

You can do <C-r>" to paste from the default register or <C-r>a to paste from register a.

Additionally:

Ctrl-y Moves screen up one line
Ctrl-e Moves screen down one line
Ctrl-u Moves cursor & screen up ½ page
Ctrl-d Moves cursor & screen down ½ page
Ctrl-b Moves screen up one page, cursor to last line
Ctrl-f Moves screen down one page, cursor to first line

Ctrl-y and Ctrl-e only change the cursor position if it would be moved off screen.