As to 'will they fit ?', the answer is "It depends". Some cars MIGHT have upgraded brakes (BMW, for example do this on the 3 series with the 'MSport brake pack'). In BMW's case, having those larger brakes means that you must have 18" or larger wheels.

Also, those wheels are for a VERY old model of car (a 2002 B6 model). The car you are looking at is a B8. The B7 (unsurprisingly) was the intermediate model. So the offset and centre hole size might be different. If centre hole size is diefferent then they just might not go on. If offset is different then they might well go on, but severely affect handling, suspension wear, tyre wear.

As to telling your insurance company : it is a modification. You MUST inform them. It is acondition of your policy. Failure to do so might mean they reject a claim, and they could even cancel your insurance (which you'd have to inform other insuarance companies about, who would then charge you the earth or run a mile)

They might charge an additional premium, or they might not.

Finally : do be aware that that car is (almost certainly) one of the ones with 'cheat software' fitted. As such, when it goes in for the recall work to make it comply with legislation (which will be next year), you might have to have an Adblue system fitted to it, or a drop in BHP, or .... well, we're not sure yet.