Install rustup (assuming using fish)

1) Proceed with installation (default)
2) Customize installation
3) Cancel installation
>2

Modify PATH variable? (Y/n)
n

Add path to fish: fish_add_path $HOME/.cargo/env

Common cmds of rustup

rustup install [stable, nightly, ...]

rustup default [stable, nightly, ...]

rustup toolchain list

rust-analyzer is available in rustup, but only in the nightly toolchain: rustup +nightly component add rust-analyzer-preview .

Install through OS package manager (from doc of Doom Emacs).