Wish I’d timed this to chip in with VSS. 270 is of course Thor’s choice. But you wouldn’t go wrong even with a 243. Easy to shoot, fallow no worries at all, plenty of lead free that works fine whatever people say. Pretty much the same applies to 6.5cm, etc etc. get a calibre you like the sound of down on your application and get on with shooting.
I can only think of one person who has never changed and will never change their first rifle (my brother) but you’ll probably end up with a spare or something that has some features you hadn’t though of, so don’t get too stressed choosing a rifle as long as the idea of it makes you smile. They all more or less work!!
My final bit of advice, which i rarely take myself, is don’t use the time not shooting to over complicate your plan to harvest deer. Once you’ve got a rifle and it shoots fine, get about and shoot it.