Oh @vickibee, I'm so sorry. That's awful.
A few things have stuck out to me, from the various posts so far. If you find being able to smell his clothes helpful, you could bag some of them up in one of those vacuum storage bags so you can access them when you feel the need. If you're happy to DM your address to a random stranger, I've got a spare one knocking about you can have, that I can post to you. You may also find it helpful if you've got any video clips of him, or even just his voicemail message, to see if you can get someone to make backup copies of that for you, but that's a job for another day.
Not having a will is a bit of a pain in the arse, but at least you're married so it should be less so than otherwise - there's a bit on the gov.uk site that you can go through to see how it should pan out. If you've got legal cover as part of your home insurance, then that might come in handy to help you deal with all that. There's also a really helpful step by step guide about what you need to do to register the death and so on, and there's the Tell Us Once scheme operating in a lot of areas that means when you notify the Council, they can tell HMRC, the DVLA and a bunch of other government departments so you don't have to.
Finally, I'm sure someone has probably beaten me to it, but Winston's Wish provide bereavement support for kids, and Cruse may be of use to you. I hope you've been getting a little comfort from all the handholding tonight.