There are two ways to work with your team. Most people start by sharing a list. It works on every plan, including Free.
Their name shows as Pending until they accept. They don't need an account first. They can sign up with the same email address.
What your teammate does: they open the bell in WeGoDoo, go to Activities and press Accept. The list then shows up for them, and Pending changes to Member.
Up to 50 people can join a list. On the Free plan, shared lists count towards your 3 lists, and the same goes for your teammate.
With the Business plan, you pay for your team in one place, and everyone gets the full features. You can only buy Business on the website.
Need more seats? Use Buy Licences on the same page. If an invitation goes missing, open the three dots on that person's row and choose Resend invite.
If you just want to work together on a few lists, sharing is enough. If you want everyone on a paid plan under one bill, choose Business. See Free, Pro and Business: what does each plan include?