I want to manually install the update. Can I force it to do so?

Apple document for update

Update your iPhone, iPad, or iPod touch - Apple Support

Exactly what update do you wish to “force”?

What happens when you attempt to update?

What happens when you attempt to update?

On which device?

What is the existing version of iOS?

Any error messages?

Jdj2021 wrote:

I can’t find a way to manually install the update. I am trying to install it on my IPhone.

And we are attempting to help you, but you seem reluctant to provide any requested answers.