There could be lot of things I can ask you to check, but my advice is to go through some car wiring troubleshooting videos on YouTube, don't hurry it. Try to understand the workings, don't look for exact issue, but try to first learn how to check simple things.
Use multimeter to check simple things, like if indicator's wiring is working, take out the indicator lamp, put multimeter on its terminals and see the readings. Its not hard, just need a bit of focus.
Once you have done some practice, then try to trace wiring for your actual issue.
Edit: Here are some links that might help to get you started
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