To put a link in your newsletter, include the entire web address of what you want to link to in your newsletter. When it is sent to your subscriber, most email software will automatically turn the web address into a link.
In case your subscriber's email software doesn't turn the web address into a link, include a note to copy and paste the link into their browser.
The newsletter doesn't allow html because some software programs will not allow html code. Instead all the code will appear or your email will be blank.