It takes a while so you have to be really consistent. I don’t actually use a clicker (it was too loud and scared him) but I make a “clicking” sound instead. Essentially, you click (with a clicker or making a clicking sound) and offer your rabbit a treat. Some people even use a clicking pen. I use tiny bits of dried papaya but bits or carrot or pellets work, too. Whatever your rabbit prefers. Do this every day until they make the association between the click and the treat. Click. Treat. Click. Treat. Eventually, you should be able to click anytime and they will come over to you. It took Olaf a few days to get it.
For spin, lead your rabbit around in a circle very slowly with a treat. They may not get it at first but keep doing it until you get them to follow it all the way around. As soon as you get them around, click the clicker and offer a treat. Keep doing this over and over for up to a week. Lead around, click, treat. Eventually you’ll notice you won’t have to lead as much and they’ll starting understanding. With time, I stopped leading and just used my hand to gesture in a circle. Always clicking as soon as he made it around. Now, he’ll do multiple spins in a row before a treat.
Tunnel? Same thing. Consistency and repetition. I lead him to the tunnel with a treat and then put my arm through the opposite end. As I pulled my arm back out he followed it through. As soon as he got the end I clicked and offered a treat. We did this over and over until he understood the game. Now, I just tap on the edge of the tunnel and he knows to run through.
It takes a lot of time and patience. You also have to be willing to take breaks and not get frustrated. Essentially, you always want to “click” as soon as a task is accomplished. That said, you may have to start some tricks in small parts and then start putting them together. Plenty of videos on youtube. Good luck!