Yes, you can.

Thanks. I've tried and failed. How do I make two calendars independent of each other? Appreciate any tips and steps. When I create a new calendar, it has all of the events in my first calendar.

You'd need to provide more details. What type of calendar do you want to create - local or network? If network, do you need an add-on or are you using native CalDAV connectivity? Is this a Google calendar?

What were the exact steps you did to create a second calendar?

I want to create two local Thunderbird calendars for myself. I opened the calendar icon on Thunderbird and clicked on the + symbol to the right. I also tried right click on calendar and then new calendar. Both created a new calendar but it has all the info/events from my original calendar. If I add events to the new calendar, they also appear on the original calendar. I want two independent calendars, each with their own events.

What version of Thunderbird are you using? The latest release version is 115.1.0. https://www.thunderbird.net/

I opened the calendar icon on Thunderbird and clicked on the + symbol to the right.

I have no idea what you're talking about. Can you post a screenshot? https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

Using TB115, to create a new calendar first open the Calendar tab. In the left pane at the bottom is a 'New Calendar' button. Clicking that button starts a wizard. Choose 'On my Computer' - assign a unique name to the new calendar, and optionally assign an email address to it if you do receive meeting invitations to that email address.

Thanks.