For Twitter it’s very simple, you just need a URL like this: https://twitter.com/intent/tweet?text=Hello%20world
I don’t know for the other platforms

writen by Luca Restagno (ikoichi on Twitter)

writen by Luca Restagno (ikoichi on Twitter)
With a bit of integration work you could use a library like https://socialsharekit.com/

writen by Benedikt