Just wanted to get some advice. I want to know if anyone could link me a good video on stripping down an M4. Also how regularly should be maintaining my gun? And what's the best type of silicone spray to use for it?
If it's newer than two weeks, let the retailer maintain it, ie send it back and get a refund. It's not actually a starter airsoft gun, even though it is a BB gun. There is a difference. If you take that to a skirmish you'll be outranged pretty severely by pretty much everyone's primary weapon and there'll be many pistols that can shoot further too. What you want is a G&G Combat Machine if M4's are your thing. Have a look on Zero One or Pro Airsoft Supplies.
If you can't return it, the only thing you'll need to do is clean the barrel. If you use alcohol swabs on a plastic barrel cleaning rod it makes it easier. It will break before it needs the internal lubrication replacing.