when you start load the page do you mean it will be load in a single particular page or any page ?

first time user entered the website or refresh the page

is the API external api or its a nextjs route ?

is the page client side or server-side ?

external API

server side

Do you have a snippet that you can share ?

And how often do you want this API to revalidate itself ?

Usually if you use fetch then you can add nextjs exclusive option to revalidate the API. Since it will cache the route by default. But if you want to opt out of it altogether then you can add cache: no-store option to the fetch.