Logic gates are the simplest electronics possible, and all more complex electronics are based on them. If you can't understand them, you're unlikely to be able to build an actual computer.
You can find a huge number of guides on the basics of computer logic on the Internet. For the simplest devices, you don't even need to know the intricacies of how electronics work in TPT, and just copy real circuits, connecting gates with wires. If you're too lazy to look for them yourself, well, that's your problem.