Dont know what to do with life

I have an offer (AAB) but im now thinking that i may not get those grades, and sometimes i tell myself that its ok if i dont get those grades because biology chemistry and physics are hard lol. But then im like, wtf do i do if i dont get the grades because ill get rejected from my offer (which im not 100% sure i want to do in the first place lol) and i dont know what else i want to apply for in clearing because its a lot of money to spend if you are still uncertain. I though gap year but i dont have the money to travel (which i want to) so i would stay where i am now which is not what i want because the money from jobs here isn’t great and i think that i would struggle going back to the ‘school life’ by the time that my gap year has ended. Not sure what my goal was writing this here but i just want to see if people feel the same as me (confused with life lol) and possibly get advice from people whom have been through this and have reached a better place
Also im not first language English so please excuse my grammar lol