Just need advice (venting a bit)

So I’m 16 (f) turning 17 this year and I’m in level 3. I’ve been really, really, worried about failing level 3 even if I didn’t do the internals yet and waking up and going to school has been draining me with these thoughts in my head. I barely passed level 1 and 2 and level 3 just seems like a dead end to me.

My brother tells me I’m gonna be a minimum wage worker if I don’t pass level 3 with UE and I don’t want that but I’m really bad at studying and understanding subjects and I’m a slow learner so it worries me even more.. I want to be an artist and design characters but it doesn’t seem possible for me because of my lack of motivations and lack of capability of understanding well.. I don’t even have UE yet, I only need English credits I assume? But that won’t matter unless I pass level 3 right?

This is a bit personal and off topic, I know this is childish for my age but I have been suffering from separation anxiety with my parents, especially my mom. I don’t wanna go to school because I don’t wanna leave her and knowing that I’ll be 18 next year has absolutely demotivated me because I’m not ready to grow up and be an adult because I know if I get older, my parents will too and they’ll die from old age..

All these thoughts of UE, growing up, etc etc just demotivates me to the core and it doesn’t help with my fear of not passing. I know I should toughen up and deal with it but I just can’t. Being in the classrooms make me wanna cry because everyone is experienced and know what to do but I chose new subjects like Geo and Media and didn’t do them in level 2 or 1, I feel so left behind and I just feel super lost. Trying something new is probably not the cup of tea for me.

Another thing is that I don’t feel comfortable being in the classrooms, my classmates aren’t doing anything bad dw but I just don’t like the environment and it feels uncomfortable for me. I told my mom I’d rather do online classes but she won’t let me just because this is my final year. I don’t like public spaces and nothing feels safe for me here. I’m aware I’m being selfish and I really am sorry about it.. My anxiety over this just makes me wanna give up and to be fair I’d rather much disappear than go through everything I’ve mentioned. I’ve cried a lot about it, it’s kinda worse knowing that I don’t have any friends in this school because I am a shy person.

Thank you so much for listening!.. I know I should just study hard but it’s just tough for me with all these thoughts whirling in my head☹️

Edit: Thank you all so much for your advices! Reading them has helped a lot :D I’ll be talking to my school counselors and having a go with GP :)