To get started, make sure you have administrator access to G Suite.
Please also note that only paid accounts have access to resource calendars so a personal Gmail account, unfortunately, won't do the trick.
Go to the administrator panel in Google and select "Apps" > "G Suite" > "Calendar."
Under the Calendar menu, you’ll see a section for Resources. Click on it.
From there you can add or edit existing resource calendars in Google. When you add a new resource, you can specify the type. Use something general such as “meeting room/conference room.”
Room resource email is written under the 'Resource email' section. Copy this and paste it to Joan Portal to add it as a room you want Joan to manage.
Now, when you book events in Google Calendar you will be able to invite rooms to your meetings, effectively booking them in the process. Rooms reserved at the time of creating an event won't show up in the list by default. This prevents double booking, which isn't fun for anyone.