How do I do"do" puja?

Sorry for the mistake in the title but I can't change it now. It's meant to say "How do I "do" Puja?" Hello all, I hope this is the right place to ask - there's a tad of backstory. My grandmother (by marriage) has sent me a small Ganesh with some sanctified water for my new home (this weekend just gone). The water is from a Mandir in Wembly, London and was sancified at a abishek to the image of Nilkanth Varni. I asked her daughter (my stepmum) what I should do with it and she said "place Ganesh somewhere in the house that faces the front door and sprinkle the water around the home". She also mentioned that houses with men should have a Hanuman too. My stepmum is Hindu in that she doesn't eat beef and has a small Ganesh and Hanuman statue on a windowsill but - as far as I'm aware - that's as far is it goes for her. She was born and raised british by Kenyan Gurjarati parents. My grandmother doesn't speak english very well so I can't ask her directly for more info as we misunderstand each other a lot. And I feel silly asking my stepmum as she isn't very forthcoming with information. I am British. I live in a very undiverse, christian-based part of Britain. The nearest Hindu temple is a 4 hr drive away. I have never been religious (although - now I'm thinking about it - I have dabbled in the Buddha's suttas, attended two Hindu temples without knowing, and attended many, many chanting yoga classes. Chanting that included Om, Shiv, Vishnu and other well know Hindu deities). I do not believe in god (certainly the abrahamic god). But for some reason that I cannot explain, I really want to do this right. Maybe it's a curiosity in the exotic. Maybe it's the idea of having some kind of ritual in my life. I'm not really sure. I've had a cursory google search for answers and have come across Puja. However, it seems *very* complex and *very* overwhelming. So far, I've lit a candle for Ganesh in the morning, when I'm fully dressed and ready for the day, and said hello and hoped he liked the candle. That's it. This must seem like absolute nonese to whomever has been living these things everyday of their lives, and perhaps I'm beyond help, having no nearby guidance or prior knowledge. Just know that I do not intent to offend and I most certainly do not want to upset anyone. I'm interested in offering food but surely there's somekind of wording/rules that goes with this? I've read that the food should be offered on a small metal plate with the righthand. But what happens to the food afterwards? How long should it remain there? Do I throw it away? Do I eat it? If so, when do I eat it?If I have a lit candle in the morning and I have to leave, can I blow it out?? (I don't like leaving candles unattended). Ganesh is in the living room so he seees most things we do day-in and day-out - is this ok? Or are there certain things I shouldn't do in front of him? Any advice would be appreciated but I understand that my complete naivety in this matter might be off-putting. I prefer to read instructions rather than watching "how to" videos fyi Thank you for reading xx