What is Thomas Jefferson trying to say in this excerpt from the Declaration of Independence ? :The Right of the People to Control Their Government . . .

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the Pursuit of Happiness; that, to secure these rights Governments are instituted among Men, deriving their powers from the consent of the governed; that whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or abolish it, and to institute new Government. Tyrannical Acts of the British King for cutting off our Trade with all parts of the world; for imposing Taxes on us without our Consent; for suspending our own Legislatures.

Does it mean everyone has unalienable rights and King George III cannot take that away from them?

Yes.

He added that people had the right to start a new government if the old government didn't respect people's rights.

thanks again

You're welcome.

Yes, Thomas Jefferson is expressing the belief that all people are inherently equal and possess certain unalienable rights given to them by their creator. These rights include life, liberty, and the pursuit of happiness. He further states that governments are established to secure these rights and derive their power from the consent of the governed.

In this excerpt, Jefferson specifically mentions the tyrannical acts of the British king, such as cutting off trade, imposing taxes without consent, and suspending local legislatures. He argues that when a government becomes destructive of these fundamental rights, it is the right of the people to alter or abolish it and establish a new government that will better protect their rights. So, yes, your interpretation is correct that King George III cannot take away the unalienable rights of the people.