This is the 12096th most frequent Spanish word.
insta
A colloquial abbreviation for "Instagram" or a form of the verb "instar," meaning "urges" or "insists."
Here, 'insta' is used as a verb meaning 'urges' or 'pushes for'.
Ella me insta a que tome decisiones rápidamente.
She urges me to make decisions quickly.
In this context, 'insta' is used as a noun referring to the Instagram platform.
Subí una foto a mi insta ayer por la noche.
I uploaded a picture to my Instagram last night.
Here again, 'insta' is a verb in third-person singular, synonymous with 'invites' or 'prompts'.