How do I write it so that the MC isn’t just facing conflict after conflict, but make it not seem like filler.
Simple, put other types of story drivers into the event structure. Discovery. Emotion. Morality. Ways to Live, and so on. The idea that stories are purely conflict comes from Percy Lubbock in 1921. It's untrue that previous stories were all driven by only conflict. Many theorists (including Aristotle) cited other things that would make a story move forward.
- Gustav Freytag argued for emotion and that contrasting emotion created the height in story.
- Aristotle argued for morality (though negative reinforcement really doesn't help his case)
- It's solidly argued by historians that Shakespeare and his contemporaries were trying to legitimize the Queen and King of the time, so morality was the central driver of the plot.
- In Chinese, Japanese and Korean storytelling, discovery and emotion were argued for in the 4-act story structure.
- In Australian Aboriginal stories and Native American tribes/nations, often the story driver is ways to live.
- Women solidly from about the 19th century to today have argued over and over for the story driver to be discovery. (White women)
- Africans have argued for the central story driver to be morality and memory.
Don't tie yourself to conflict only. Discovery often slows the story down significantly. Being addicted to conflict isn't always good.
Conflict as a story driver has its downsides, including that it often only allows for one or two emotions. That in order for things to get bigger, you need to amp up what? The anxiety and depression in the reader, but it's also good to have the character stop and reflect and smell the roses, to apply the lessons they learned.
And if you need to demonstrate what they've learned in a slower moment, discovery, emotion, morality as story drivers are stronger than conflict for that sort of thing. (Sometimes ways to live too.) You are 100% allowed to not have conflict as the story driver. Switch it up. Bring out other emotions... if you want wonder, then discovery is your ticket in. If you want thinking, then you probably will do better with morality questions. If you want to heighten a love scene, then playing with emotion might be better. The primary story driver can be different and still heighten if you play your cards right, but you don't need it to be conflict in all scenes. Conflict can feel EMPTY without those other story drivers because those other story drivers are older than conflict.
I get that stories need a problem or something to resolve or a task to do
Not always. It might be good to consume some slice of Life stories too and see how they work. Also, I have to say Indigenous North, central and South American especially coil stories defy this idea. Some of them live only on tone. Braided essays also defy this.
For time skips, you use objects that change over time. Baby grows up, trees change, seasons change. Use objects tied to time.
Basically, what you're asking for is story theory and there is a ton of story theory out there as tools for you, but I think it would benefit you greatly to get out of the US/UK mindsets and go exploring into the greater usually non-English part of the world. Out there, beyond the English-bound borders you can find toolsets for making a long slow scene oddly interesting. How to make something oddly satisfying. How to make a twist worth a person's time. When to cut the conflict to create greater emotionality. How to command tone until your writhing because they did it so well. How to cut away all setting so it no longer matters. How to make thematic development sing under your fingers. How to play with structure so you're not married to a bunch of white men who mostly created it to hate on women (yes, I have the references for that).
Explore and expand your toolbox, and you definitely can pace out your event structure by learning like how Honey and Clover managed to make you warm and fluffy and that ending gets you. How to make a conflictless, problemless event structure. How slice of life really works.
Read/consume stories not only to enjoy the book, but to also ask, "How did they pull that off?"