You're meant to shove an alarming amount of air into your tyres. The little pump sold with bikes isn't actually what you use to keep your tyres inflated day by day. That's just to let you limp home after a puncture. You really need one of the two-foot tall beasts with a pressure gauge and the foot plates at the bottom, and when you've finished pumping it, when you inevitably nudge the clever little thingmy on a Presta valve, the air will come rushing out so violently that if you don't think it's about explode in your face, then you've not really finished pumping it in.
You need to buy new clothes.
You don't need to buy new clothes.
The above two may seem, at first glance, to be a little contradictory, but what I mean is that unless you were already doing monkeybuttloads of exercise, you're about to become significantly leaner than you currently are. If like me you find it almost impossible to throw away or charitably donate clothes in wearable repair, then your wardrobe will have the things you wore years ago. You know, when you were just at the end of that 19 year grace period that booze and pies give you before they notice you're there. Thus I am frequently clad in what was de rigeur at around the time Bruce Willis was crying inside space rocks.
You don't, however, need to buy cycling specific clothes, although there's a slice of the sartorial pie chart that happens to be practical for cycling and you're likely to gravitate to that soon.