Whether you love it or hate it, "Stairway to Heaven" is one of the most popular rock songs of all time. It was originally written for Led Zeppelin's 1971 album and has become a staple on radio stations all over the world.
The song is a critique of an overly materialistic society, suggesting that spending all of your life collecting possessions won't make you happy in the afterlife and will do nothing to help you find a sense of peace and meaning. It is also a metaphorical song, with Plant using his signature vague and poetic style to express the lyrics.
In the first verse of the song, Plant sings about a woman who is extremely materialistic and obsessed with her appearance. She is always splurging on the best clothing and shoes, and she's constantly making purchases that are more than she can afford.
Her pursuit of materialism is causing her to live an unfulfilling and unsatisfying life, and she's convinced that the only way to make it better is to buy her way into heaven. However, this doesn't work, and the only way to find happiness is to follow your heart.
This idea gets explored throughout the rest of the album, but it comes to a head here. After preaching this epiphany to the choir, 2D then addresses the woman again and tells her that she should follow her heart and stop chasing things she can't have. She should stop wasting her life and start focusing on what she wants instead of worrying about what others think of her. She should stop chasing drugs and alcohol and start following her dreams.