If you have a subscription to one of the cloud-based solutions of Project you won't see an option to install it unless you have been assigned a license by your company.
Step 1: Sign in to download Project
Go to https://portal.office.com using your internet browser (Microsoft Edge is the best option!) and if you're not already signed in, select Sign in.
Sign in with your Microsoft Office365 Account Details.
From the Office home page select Install Office apps > Other install options.
Under Software, select Project. Choose the language and the bit version you want, then select Install. (To install 64-bit, under Version, select Advanced, choose 64-bit, and then select Install.)
Project should now begin downloading. Follow the prompts in Step 2 to complete the installation.
Step 2: Install Project
Depending on your browser, select Run (in Edge or Internet Explorer), Setup (in Chrome), or Save File (in Firefox).
If you see the User Account Control prompt that says, Do you want to allow this app to make changes to your device? select Yes.
The install begins (please ensure you have a strong internet connection, and don't interrupt the installation process!)
Your install is finished when you see the phrase, "You're all set! Project is installed now" and an animation plays to show you where to find the Project app on your computer.
Follow the instructions in the window to find Project, for example depending on your version of Windows, select Start and then scroll to find Project from your list of apps.