How long does the effect of fillers usually last?

Hello. Lately, I have been considering getting fillers, so I am writing this post to share my thoughts and ask a question.
First of all, my biggest concern is forehead fillers and chin fillers.
I've always been self-conscious about my sunken forehead, but as I get older, it feels like it's sinking even more...
When I look at my profile photos, I think I would look younger if my forehead were fuller, so I keep finding myself interested in forehead fillers.
Also, I want a pointed chin, but it seems difficult to achieve with dieting alone, so I am interested in chin fillers.
If only I could get nice fillers in both my forehead and chin, I would be so happy every time I take a photo. ㅠㅠ
If I get both areas done at once like this, how much would it usually cost?
I'm also curious about how long forehead and chin fillers last!