when is it too late to get into science and maths?

when does your brain become concrete in terms of plasticity?
are there any ways around this?

to personalise this thread
i'm 27. i studied social sciences because i flunked maths because i smoked lots of weed when i was 17.
my father is an EE and my brother is a EE and coder.
I've enrolled in an entry level maths course at a distance learning university and plan to get to a second level.
I might then unironically start a STEM degree, is this biologically even feasible