A Twitter profile has only one field for directly linking a website. But the bio converts the text of URLs into clickable links, which lets you add there your Buy Me A Coffee page, social profiles, your newsletter or blog, and more.
Just edit the profile and type or paste the URLs into the bio.
Be sure to omit
https:// as the field accepts up to 160 characters. This way the bio is more compat and easier to read, and the URLs are easier to remember. A nice touch is to preceed URLs with descriptive emojis such as a coffee cup or folded hands for the Buy Me A Coffee page, a globe for a website, a mailbox for a newsletter, books for an author page, a newspaper for a blog, and so on.
Here’s what a bio with such links may look like in a Twitter profile. It’s too long but gives an idea of what’s possible.