You may see a 'Stop, you should wait to install Office.' error. See How to use Office 2013 suites and programs (MSI deployment) on a computer that’s running another version of Office.
There is one exception to this: If one of the two products is installed through MSI (which is common for volume licensed products), these two can run side-by-side. If you have a Microsoft 365 subscription or non-subscription version such as Office Home and Business 2021, 2019, 2016 or 2013, in most cases you can't run these versions together on the same computer. Note: If not otherwise stated, the following statements also apply to individual apps such as Visio and Project.