fix H1s per seo suggestions

reference/data-analysis/kibana/canvas-functions.md

@@ -1,11 +1,12 @@
 ---
 mapped_pages:
   - https://www.elastic.co/guide/en/kibana/current/canvas-function-reference.html
+navigation_tile: Canvas function reference
 products:
   - id: kibana
 ---
 
-# Canvas function reference [canvas-function-reference]
+# Explore Canvas functions and its expression language for Kibana [canvas-function-reference]
 
 Behind the scenes, Canvas is driven by a powerful expression language, with dozens of functions and other capabilities, including table transforms, type casting, and sub-expressions.
 

reference/fleet/data-streams.md

@@ -7,7 +7,7 @@ products:
 navigation_title: Data streams
 ---
 
-# Agent-created data streams [data-streams]
+# Elastic agent data streams for Fleet [data-streams]
 
 {{agent}} uses data streams to store time series data across multiple indices while giving you a single named resource for requests. Data streams are well-suited for logs, metrics, traces, and other continuously generated data. They offer a host of benefits over other indexing strategies:
 

reference/fleet/elasticsearch-output.md

@@ -7,8 +7,7 @@ products:
   - id: elastic-agent
 ---
 
-# Configure the {{es}} output [elasticsearch-output]
-
+# Configure the {{es}} output for Elastic agent [elasticsearch-output]
 
 The {{es}} output sends events directly to {{es}} by using the {{es}} HTTP API.