On most older vehicles changing the air filter is pretty easy but on some of the newer and more exotic models it can be a little more challenging. Check this YouTube video https://www.youtube.com/watch?v=mo87vl53q7A
for instructions. You may also want to check out a good program like Automotive Wolf
to keep a comprehensive vehicle maintenance schedule log book for your vehicle. Then you will know exactly when to service your vehicle and have it send you reminders so you never forget.