Can someone help me with custom hook code?

Hello. I want to create a website where people can upload their social media information and then use the website as their online business card. I am very far in the development of the website but now I have to find a way for people to write their instagram username for example and when they do the dynamic page should update with a link to their instagram.

I think that first I should have a place where people can write their usernames for different social media websites. Then this information should go through a hook which changes their username by adding “https;//www.instagram,com/” in front of their username. And for every box there should be a new code for adding the appropriate link. So for example:

I write my instagram username in the box - daniel_lachev - and I click submit
Then the code comes into play and adds “https;//www.instagram,com/” in front of my username and it is then send to the database as “https;//www.instagram,com/daniel_lachev”. Then of course the link is connected to the dynamic page of each person.

Can someone make this code? I will be really thankful for that.