To be fair the stuff you cut down now probably won’t be for this winter but the one after. What’s the wood from work? Burning proper crap is just asking for trouble.
I have a petrol husqvarna. I think as a rank amateur (I include myself in this) you don’t want to be tackling anything much thicker than the bar length of the saw. It is possible but it should not be your first job you ever tackle!
Usual H&S caveat – chainsaws are potentially scary. I have access to some full on kit (table saws, planer thicknesses, plasma cutters, big routers etc) and I still think the chainsaw is the one that has me most concerned. Mainly because of the unpredictability of the stuff you will use it on. Safety gear is a must too. A course is not a bad plan and some brands (stihl) won’t sell to you unless you have a ticket.
It might be a baby electric jobbie is all you need to keep on top of your freebie wood and get someone else to chop up the tree.