ik that this is probably on here already, but how do I manage my stutter?

ik that this is probably on here already, but how do I manage my stutter? I'm 15f, and I'm a sophomore in highschool. I have a stutter that gets worse with stress, basically the word gets stuck, my brain gets stuck, and I'm just standing there looking like a dumbass with my mouth open until the word comes out. I've had it my whole life, and it's recently gotten way worse(stress and an increasing amount of social situations, I am really anxious in social settings.) it wasn't too bad during sophomore year and I was able to control it. it is so bad now, and such a dramatic change that I an afraid that people think I'm faking it. I went to olive garden a few hours ago and I couldn't even finish saying my order. I had to point at it on the menu and I felt so stupid. I have a presentation for my final project in English class where I have to talk about how I have grown accedemicly, socially, and as a person this year. I have to present it to the entire class and some seniors. I am worried that I am going to stutter my way through it again, like I do every presentation. we always time our presentations, and mine on average are 2 minutes longer than everyone else's, with the same length script just because of how much I stutter. I can't get therapy for it, because we can't really afford it and I think my parents think I'm faking it becasue of how quickly it's gotten bad. it's also really hard to talk about it to people because of how much embarrassment it has caused me. I just need to fix the stutter or have ways to control it so I can get through this presentation and to be able to talk to people better later in life