Not quite sure about your last question, bro! Do you want to make a lamp that "heats" like the Sun? Or do you want to create a GrowBox from available materials to ensure complete darkness during the night? If you have no experience, it's better to turn to ready-made solutions for lamps and tents!
An old refrigerator works great as a tent.....clean it out....set up air circulation in it.....ventilate it to remove excess moisture after washing....the white walls inside the fridge reflect light from the lamps really well, so you won’t have any problems with wall finishing in the fridge.
Making lamps yourself isn’t the cheapest thing to do if you don’t know exactly what LEDs and drivers you need. Most people either use ready-made solutions or they know exactly how many LEDs, what power, how to place them on what surface, what power to give them, how to connect them...in parallel or in series....what cooling method will be used for the board..... all of this will take you a lot of time and money until you find what you need and solder it all together by hand. But I made my own light; it was a year of trial and error, and I spent a lot of money before I found the perfect solution for myself! 😇👆
And don’t forget to choose the best answer author, in your opinion, to your question. It’s important for the community and for our competitions, my friend! 😇👌
Good luck, brother! ✊😇