WREN:

Go to your local computer store.

Ask the man 'Show me how to use a LAPTOP, please". You obviously want to go on the internet. Ask the man if the laptop comes with stuff inside so you can go home, plug it in and go on the internet. If it doesn't ask him to show you how you can do this.

He will show you.

Watch what he does. Ask questions. Don't buy it until you completely understand what he has told you.

Practice on the laptop in the computer store.

Buy the laptop.

Bring it home, plug it in.

You will be all set.

See??? small words. BIG EXPLANATION!!! lol

I'm not sure if these are still sold, yet an Emachine (for a desktop computer v. laptop computer) would be a pretty easy one to set up and use.

Along the lines of what Melody suggested, you could also visit one or more of the Big Box stores that has computers on display, and meant for customers to tinker with.