I am so sorry to hear about your loss Isabella. I lost an immediate family member about 2 months ago. Personally I don't believe time heals all wounds (no offense to Rabbit).
My family member was like a best friend. I cared for her daily and watched her steady decline which was hard enough to endure, as I'm sure your father's was for you.
I cry still a few times a week when I go to check on her and remember she isn't there, or think of how she would've reacted to something on TV or something that happened during the course of the day.
I'm fortunate to have my mother to talk to about things, though I tend to internalize more so I didn't want to discuss it as much as my mother did.
The first 2 weeks were the hardest for me. I had restructured my life around providing care for this person. Aside from adjusting from the loss itself, I had to completely adjust my daily life.
In regards to the sadness, I can't say I'm any better today than I was the night she passed away. As my mother pointed out though, I don't think I'd have ever been Ok with her dying, regardless of if I knew when it would happen or not.
It's funny though, when I do things or see something, I can still hear what she would say and that brings me some comfort.
I think the best you can do is remember the good times you had with your dad and try to honor what values or teachings he may have passed on to you, by how you live your own life.
My fear is that one day I'll forget her smile or laugh or won't hear in my head how she most likely would've reacted to something.
If your father had a passion for something, you could always try to get involved with that in some way, so that you still have some sort of connection to his life.
Sorry I can't be more helpful. Everyone deals with death differently and the same person reacts differently from one loss to the next. There's no set answer to easing your pain I'm afraid.
Time most likely won't heal that wound and the loss will never stop hurting. I miss my grandfather who died in the early 90's just as much now as I did then. Maybe even moreso.
But you will get over it enough to start enjoying life again. Without death, life has little meaning. Your father no doubt would want to see you happy and healthy and thriving. Give yourself the time you need to grieve the loss. Just don't let that loss begin to consume you (it will feel like it is in the beginning).
Honor your dad by mourning his loss and then live your life to the fullest as best you can. I wish I could offer better wisdom than that, but I'm still trying to figure things out for myself.
Don't hesitate to message me if you just need to vent to someone.