If you want to check the levels of some of your vehicle's essential liquids, here is how to do so and why it is important…
Antifreeze works by raising the boiling point of the coolant. This helps prevent the engine from overheating, which can damage the engine and make parts start to deteriorate faster. For this reason, it is incredibly important for the health of your vehicle. To check your antifreeze levels, look for a tank near the radiator (check your vehicle's manual). The tank should have levels on the side. Make sure these levels are full.
In order to check the transmission fluid on an automatic vehicle, you need to make sure that the engine is running. Typically, the dipstick for transmission fluid is found somewhere near the oil dipstick but isn't as noticeable or obvious. Consult your vehicle's manual if you have trouble locating it. Because transmission fluid doesn't run out, a low reading on your transmission dipstick means that there is a leak and that you will need to take it in to get it fixed. Transmission fluid will look red/brown when it leaks.
Similarly to transmission fluid, brake fluid doesn't run out, because it is in an entirely sealed system. This means that if you are low on brake fluid, there is a crack somewhere that is causing a leak. Brake fluid is essential to making sure your vehicle can brake properly, which means it's very dangerous when this gets low. Check your vehicle manual to find out where the brake fluid level is (it's going to be near the brake fluid reservoir). If this level gets below two-thirds full, then you definitely have a problem.
Power steering fluid
Power steering fluid isn't as essential as brake fluid, and you can get by without it. However, the added difficulty to steering could be dangerous in a situation where you need to quickly maneuver your vehicle to avert an accident. For the essence of safety (and the added convenience that power steering adds), you should always make sure that your power steering fluid levels are full. To check this, look for a small tank that is near your vehicle's firewall, near the bottom of the windshield. The levels should be on the tank.