Program installation lock for unauthorized persons?

Ka
5

Sry, I hope that my question is correct and understandable. If not, please take your time and write the question correctly.

So it's because I'm the lpt. Wait for a friend and help in case of problems. The friend of her, but simply installs system programs, where I said the no way. Because he has to blame, she does not have to suffer. Does anyone know how to do that?

Device: Laptop

OS: Windows 10 Home 64 bit

Bu

Give your friend's account a password and make you a normal user without admin rights.

La

Create user accounts, because if he only has Gadtzugang, he can no longer install, unless the admin allows this

Li

The girlfriend has to decide - either you install (system) programs or the friend of her.

Does it make the friend of her, you do not start the laptop anymore.

Ka

He does not care what she says, he makes it easy even though she no longer wants him to do it. And I also want to password-protected the BIOS, but I do not know how, certainly in the BIOS

Ka

It never installs anything, the lpt mainly uses it for youtube.

Oh man, today I have to go there because of a problem. (I only waited intensively 2 weeks ago.)