Your email address is a valuable document that you should be careful about. There are different ways to deal with this problem. Many people acquire a “spam address” to use for this purpose, for example an extra Gmail address or an address from another free service. However, that means you may have to wade through the junk on that account when you log in to get a confirmation message.
Another possibility is to use a one-time address, an email account that is active only for a short time. You can send and receive e-mail messages to and from this address as long as it is valid, which may be enough to register on a web page, for example. When you no longer need it, you can delete it if it doesn’t expire by itself.
There are many such services and here you will get examples of some. However, it might be worth pointing out that you don’t know what these services do with the information that passes through them. It is therefore advisable to immediately change the password on, for example, a web page that you used a temporary address to access.

1. Mailpoof
The service www.mailpoof.com is available in Swedish and you can choose your address. Received email disappears after 24 hours.

2. Email deck
On www.emailondeck.com you get an email address that the service chooses for you. It works as long as you have the window open.

3. 10 minute email
The service www.10minutemail.com offers an email address that expires after ten minutes. You get an inbox and have time to receive, for example, a verification code.

4. 10minemails
On www.10minemail.com/en you also have ten minutes to receive a response message and, just like for the previous service, you can extend the time.