I am 18 years old and I really adore the heck out of this 21 year old. Any ideas on what I should do? Ladies?

I've known her for 3 years and I currently work my summer job with her but we both do different things. Every time I talk with her I pray it never ends. No bs but she truly captivates me and I will do anything for her. I want to embrace her, hold her, and encourage her future endeavors. She genuinely means the world to me and I would be honored to have the privilege to give her the best which is what she truly deserves. If she says yes and gives me the chance, she makes history by becoming my first girlfriend. I would hate to lose her to another man.