Open the demo account
Open Google's demo-account help page linked below. Under Access the demo account, choose Google Merchandise Store (web data) and sign in. Google adds the demo account to your Analytics account, creating an Analytics account if needed. Use the account selector to return to the demo later.
The store sells Google-branded products. Google says its demo data is obscured, so treat it as practice material. Don't use the store's figures as targets for your own business.
Exercise 1: find where visits came from
Your question is: which recorded traffic source brought the most visits during one week? Open Reports and find Traffic acquisition. Choose a complete week, such as the previous Monday through Sunday. In the table's first-column menu, choose Session source / medium, then sort Sessions from largest to smallest.
A session groups activity into a visit. Source / medium describes where a visit came from and the type of traffic. For example, google / organic means Google unpaid search. Write down the leading row and its sessions, keeping the date range beside the number.
Now open the date picker, turn on Compare, choose Previous period (match day of week), and select Apply. Did the same source lead in both weeks? If its visits changed, write that observation down. You haven't yet shown why it changed, or whether those visits led to purchases.
Sources: Google Analytics: Traffic acquisition report and its dimensions · Google Analytics: compare date ranges
Exercise 2: find a frequently viewed page
Turn off the date comparison, keep your chosen week, and open Pages and screens in Reports. Select Page path and screen class in the table. A page path is the part of a web address after the domain, such as /shop/. Sort Views from largest to smallest and choose one page to examine.
Views counts page displays, including repeat views. Write down the page path and its Views total. Then explain the number in your own words: this page was displayed this many times during the selected week. It doesn't mean that many different people saw it.
Think of one question the number leaves unanswered. For a product page, you might ask whether readers added the product to their cart. For a help page, you might ask whether readers found their answer. High views alone won't answer either question.
Sources: Google Analytics: Pages and screens dimensions and Views
Write a short note you could explain to someone else
Use this fill-in template: 'In the Google Merchandise Store demo, from [start date] to [end date], [source / medium] had the most recorded sessions: [count]. The page [path] had [count] views. Next I'd check [one question].' Replace the brackets with what you actually see.
Add the report names and any filters you used. Close the reports, reopen them, and try to reproduce your note. If the numbers differ, check the property, dates, comparison, and filters before changing your conclusion. This exercise helps you explain exactly what you counted.
What can't you practice in the demo?
You have Viewer access. You can read reports and adjust how you view them, but can't change the property's tracking settings. The demo also blocks report and exploration exports and access through the Analytics Data API, which lets software request report data.
To practice installing tags or checking a form-submission event, use a separate property and a test website you control. An event is a recorded action, such as a successful form submission. Reading demo reports doesn't test whether your own website sends those actions correctly.