Hi @indeed_2000,
if you make a search on Google you can find much documentation about Splunk graphs and charting.
I hint to start from the youTube Channel (https://www.youtube.com/c/Splunkofficial) where you can find many useful samples: e.g. https://www.youtube.com/watch?v=K2SB0Bk-ais.
My hint is to see some video and then try, try and try again.
Anyway, remember that the problem isn't graphing but always searching, My hint is to work on searching knowledge, and then try to display results in graphs.
The Splunk apps can help you in this, starting from the Splunk Dashboard Examples App (https://splunkbase.splunk.com/app/1603/).
Ciao.
Giuseppe