Affordable beginner treatments suggestions?

Dear skin care lovers, I am 19 and new to the skin care world and my routine at the moment is very simple (i added the products i use below). I don’t wish to add too many products to it and i’m trying to keep it as accessible and affordable as possible. I am looking to include some sort of serum or treatment for hyperpigmentation and texture. And maybe a product for under my eyes to add to the evening routine (i have very dark under-eye circles since i was a child). Do you have any suggestions for affordable beginner products? And also when/how/how often to use them? I can’t wait to see your suggestions 🥰