My main reason for denial for being ftm is that I believe that because my father died, so I psychologically wanted to replace him; and that's why I'm in this "phase". The thing is, I've been questioning for years, and I've always felt like this. I want to cut my hair too but I don't want to look like him because it will make my mum upset. I can't take it anymore though, and I don't know what to do. My dysphoria is really bad. Thank you.
Are you sure your mother would be upset if you looked like your father? Try to see the positive... she would find a "new" son. ... And that would be way better then to lose you as well (*hug*)
If you cut your hair short, you're just going to look like you, but with short hair. If you look like your father when your hair is short, it's because you already look like him now. I don't think it'll be a drastic enough change for it to upset your mother. If you're still concerned, could you try talking to her? I know it's hard to feel confident that you're trans, but I don't think it's likely that it's a phase. You said it yourself, you've always felt like this. Usually when people feel ftm for years of their life, it doesn't go away. Get your hair cut and see how you feel. Try binding if you haven't already, and if you think it would help. You might find that it brings you a sense of comfort in your body that you didn't even know you were missing (or it might not, and that's okay too). Small, reversible steps like haircuts and binding can really help you figure out what's right for you. Personally, the more steps in my transition I took, the more comfortable I felt, and the more I felt like I wanted to keep moving forwards. You might have the same experience, or you might find that you're comfortable after making only a few changes, but you probably won't know until you start trying things out.