You don't need a ton of specialized gear to enjoy your bike. And you certainly don't need to buy every bit right away.

Make sure you focus on the safety equipment and the maintenance equipment first. A bike shop will charge a fair bit for repairs, and often it will be cheaper to buy the tools and do it yourself. Then the next time it comes up, you have the tools. If you're not sure how to do the repair, check your local library. Ours has a good half dozen books on bike repair on the shelves at any given time. And well, safety equipment is there to prevent expensive medical bills. A bike light or a helmet is a lot cheaper than a hospital stay. Note that a water bottle is safety equipment. Dehydration is dangerous.

If most of your rides are under 10 miles, regular pants or shorts will be fine. I have yet to go farther than that, but it seems like a fair number of people can handle even longer distances in regular clothes.

Oh, and tailor the special equipment to what *you* are doing. If you're in the upper midwest, and the nearest mountains are hundreds of miles away, mountain biking isn't realistic. If you're in Pennsylvania and every trip you take features at least one mountain and normal Pennsylvania roads, racing isn't realistic. Special "sports bars" and "sports drinks" can be useful... if you're doing things like a century race on a regular basis. If you're not, people ate regular foods for millenia. Most people still do. Regular food still works when you bike .