Musical instruments are challenging to master and to craft. You should consider
speaking with a professional, whether the instrument is acoustic, stringed, or
percussion. High Quality Items Worth The Price.
The best start is to read books on the subject. Get some titles from web searches, ask for them at your library.
Try searching for "Electric Guitar Building and Wiring Tips".
You can start with a kit, but you get a better guitar if you learn before making mistakes.
You can get books and plans. Ask at your local library, they often have a lot of books that don't stay on the shelves long, always out on loan.
Google MIMF to find the Musical Instrument Makers Forum. They have a lot of helpful free info.
You can buy kits on eBay - probably the easiest start.