doc: specify how fs.WriteStream/ReadStreams are created

Alternative to #33841

Co-authored-by: zombieleet <zombieleetnca@gmail.com>

PR-URL: #34188
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

doc/api/fs.md

@@ -654,8 +654,8 @@ added: v0.1.93
 
 * Extends: {stream.Readable}
 
-A successful call to `fs.createReadStream()` will return a new `fs.ReadStream`
-object.
+Instances of `fs.ReadStream` are created and returned using the
+[`fs.createReadStream()`][] function.
 
 ### Event: `'close'`
 <!-- YAML
@@ -1079,6 +1079,9 @@ added: v0.1.93
 
 * Extends {stream.Writable}
 
+Instances of `fs.WriteStream` are created and returned using the
+[`fs.createWriteStream()`][] function.
+
 ### Event: `'close'`
 <!-- YAML
 added: v0.1.93
@@ -5874,6 +5877,7 @@ the file contents.
 [`fs.chmod()`]: #fs_fs_chmod_path_mode_callback
 [`fs.chown()`]: #fs_fs_chown_path_uid_gid_callback
 [`fs.copyFile()`]: #fs_fs_copyfile_src_dest_mode_callback
+[`fs.createReadStream()`]: #fs_fs_createreadstream_path_options
 [`fs.createWriteStream()`]: #fs_fs_createwritestream_path_options
 [`fs.exists()`]: fs.html#fs_fs_exists_path_callback
 [`fs.fstat()`]: #fs_fs_fstat_fd_options_callback