You can access the Investing Calculator at the link below.
The Investing Calculator is also available inside your Ramsey+ membership. To access it, sign into your account at ramseyplus.com. Once you're signed in, look in the menu on the left and select "My Money". One of the options there is "Calculators". You can find the Investment Calculator there.
If you're on a mobile device, select the profile icon in the upper right corner. On the profile page, select "Member Benefits". This will take you to the web app version where you select the menu icon in the upper left, and then choose "My Money", and "Calculators".