She has never initiated anything

I have been dating someone for a few months and have started to notice that everything is initiated by me. She meets when I suggest that we go out and agrees to everything without offering any inputs of her own. If I don’t message, she won’t say anything. I tested this for a few weeks and once went for almost ten days without hearing from her. I am starting to wonder if this is a one-sided relationship where she expects me to drive everything and do the hard work. If she doesn’t put in any effort, I worry that this will soon start to tire me. I am already questioning whether she really wants to be with me or is just doing it because she likes the idea of being in a relationship.
You’re right about it becoming a problem if you start to feel like the only one putting in the work. The sooner you have a conversation about this, the better. If you have doubts about what she wants from this relationship or if she wants to be with you, they are serious and have to be addressed. If she has no response, you will know that your worries aren’t unfounded. There may be valid reasons for her reticence, of course, and it’s possible that she needs time to open up and be more comfortable with initiating anything, but this can’t happen without her being able to articulate the problem. If that doesn’t happen, being in love won’t be enough for either of you to sustain this beyond a point.

How do I talk to someone without coming across as creepy? I want to tell her that I really like her, but don’t know how she will react.
If you think you may sound creepy, it’s possible that you will. Why not approach this person as someone you would like to get to know, and ask her out for a cup of coffee? Allow her to get to know you better before you discuss your feelings.