Grade thresholds

So like it seems like Im ALWAYS getting a minus 1 or 2 in EVERY subject is sitting for. For example the sciences out of 160 I'll ALWAYS get a maximum of 159. I was wondering if grade thresholds ever actually bump up your marks to a 100. If they do, whats the minimum marks required out of 120 to get that 100. Also, do you obtain highest in the country and highest in the world according to you raw marks? If that's the case then I wont get anything because there must be someone out there who always gets the 100%. :( Im like REALLY terrified of this because my family is like SUPEEER strict and requires a minimum of 1 top in the country to breathe 😭