Bike maintenance

Hi,
So I’ve been active here so may have seen some posts. Picked up an aprillia rs125 last weekend. So the dealership never said if it needs a service or not and stupidly I never asked. So I’m now wondering what needs to be checked. I just need some general advice on how everything should look what need regular topping up etc. when I picked the bike up I sent pictures to a friend who has plenty of bikes he said it all looks good and clean also fresh break pads on the back and front ones look good aswell. Tyres look good to however chain and sprocket I’m not to sure what to look out for. Any tips or advice would be approached just things to look out for and keep on top of
Thanks