Is it possible to remote access someone?

The initial answer is dead wrong. You can allow remote access, but this is NOT NECESSARY for people to gain remote access to your devices. People can illegally gain access by finding holes in the security of your network and devices, and this is happening constantly. In fact, your publicly known IP address is being attacked at least every 30 seconds.

The number 1 risk is that your device is connected to the internet. Going to websites, that are not well known and trusted websites, also increases your risk by increasing the chance that your PC will have scripts downloaded, without your knowledge or consent. Porn sites are notorious, but many sites are dangerous.

To help prevent attacks, keep your anti-virus software definitions up-to-date. It is a good practice to NOT operate as your PC's administrator. If you operate as a user with non-admin privileges, the scripts that are put on your system will have to be higher level programs in order to gain access to the administrative rights that allow changes to be made to your PC. The changes made are usually to make your PC even more accessible to outside threats.

One last thing-- Back up all of your music, videos, documents, and photos to an external drive that is NOT left connected to your device.

GOOD LUCK!! I could keep writing, but I have work to do....

"Yes. But they would have to tell their computer to allow the remote access attempt."

The above is the original answer.