What exactly do you mean? You mean on a landing page a person fills out "www.mycompany.com" and you save it as a Lead token? Or do you mean you set a My token with a URL?
You can refer to this reference article to see the difference between the types of tokens, if you are doing a My token.
Either way you're doing it, you can change the token into a hyperlink. There is definitely a way. BUT a trickier question is which methodology you choose if you're trying to track the link. Like that article I posted says, text tokens don't have Marketo click tracking in the email. If it's a rich text token, that will be tracked. If you're using a Lead token, there are a few different options for how to make a link.
The following in the HTML of the email would be one solution, but I believe the link would not be tracked:
Sure! In that case, it's easier.
You can open the email in the normal WYSIWYG editor. Select the text that you want to become the link, then click the button to insert/edit link. As the link URL, put the following:
Note that this is dependent on how accurate that field is for all of your leads. If the field isn't complete for all leads, that will end up being a broken link, or might populate with something presumptuous like google.com.