I want to know how i modify hyperlink in Microsoft SharePoint.
Hope you are trying to achieve this in the list columns. If so, you cannot extend the character length of URL column.
If you want a clickable link in the list view, one option is to store the url in text field and use a calculated column to create a link. Check the below link on how to do this.
https://ootbtutorials.com/2016/04/17/sharepoint-calculated-fields-links/