I'm not talking about mind-uploading, but rather about connecting your consciousness to the computer to be able to live inside it.I'm talking rather about advanced bci, so you have all the experiences, senses you'd experience in real life but instead in video game/software.(in this computer)
VR Headsets are a start, if you need to you can go deeper
If you are talking of connection, our brain is in itself a massive computer, with sensory input affecting our thoughts and consciousness.
So to be inside a computer, you only need to 'hijack' the senses in order to be inside one.
The purpose of VR headsets is to give Sight and Sound senses to be convinced they are inside a computer environment. These are readily available. However the brain also receives other senses:
- Touch - these can be manipulated with computerised pressure suits
- Temperature - again, suits could accommodate this
- vibration - sound is a form of vibration
- electric fields - can easily be adapted
- Smell - a harder one, there are efforts to digitise smells
- Taste - similar to digitising smells
If you need more, you need to go deeper, and therefore you would need to hijack our nerve system directly, possibly at both the brain stem and eye stems. Getting electrical signals from these and diverting them to a computer, while providing altered electrical feedback form the computer, would allow us to 'be' inside the computer environment.
Be prepared for unpredictable results though, our nerve system has been slowly evolved over billions of years - you would need a pretty good computer to interpret so much complexity, and respond with proper responses.
This answer assumes you want to isolate the mind/consciousness of the user from their physical body while using the computer-brain interface
I will borrow some technology from the Anime Sword Art Online, which should be quite close if not exactly what you are looking for. The following image shows a Nerve Gear, the first Full-Dive VR-Headset.
It uses high-density microwave transceivers to transmit information to the users brain and blocks outgoing as well as incoming movement signals and other sensory information (such as the sense of touch), to ensure the safety of the user. While in the virtual world it is impossible to control your physical body, your mind and consciousness are completely separate from your actual body. Just start an application via a voice command or similar and you are completely in your virtual world, whatever that might be.