The Real Madrid goalkeeper also said he was looking forward to seeing Kylian Mbappe and Vinicius Júnior hit top form together under Jose Mourinho at club level.
Courtois spoke to reporters after Belgium came from behind to beat the African champions and reach the last 16.
"We played against the current African champions, on the pitch, because in the offices it's another matter. They're a very good, very strong team. They hurt us early on, they scored a good goal. Then I think we were better, we didn't have that many clear chances, but we did feel we could equalise.
"Although with the second-half goal I did feel the game had gone against us. We couldn't create chances. The boss made his changes and we know that's how football is. One goal and everything changes. I've experienced that many times with Real Madrid, so today I believed. We equalised and then we finished it off with the penalty so we didn't have to go to penalties," said the Belgium goalkeeper.
"We had the penalties prepared. The second goalkeeping coach was already organising everything. Both teams were heading for penalties. Almost nothing happened in extra time. And in the end that penalty arrived," Courtois added on Belgium's dramatic comeback.
Courtois also discussed his key save against Senegal while his side trailed 2-0.
"It's a tough game personally. Because you get very little coming at you and they score two goals. But you have to keep believing, and I think I made a good save against Mane, and right after that we scored. Personally, it's nice to see that. The desire and the effort of the team until the end is another thing. We played a great game. If we get the USA, they play at home, but at a World Cup nice things always happen."
The 34-year-old also reflected on his standing within the Belgium squad.
"It's a source of pride to be here. I have more World Cup appearances than anyone else in Belgium. Hopefully I can add to that a little more. We might get Spain in the quarter-finals, so we'll see what happens there. We'll see if I'm still with the national team in four years. But the truth is playing a final World Cup in Spain, which is my home, would also be nice. But those are things for later on."
Courtois also touched on life at Real Madrid.
"I've followed (Marc) Cucurella on Instagram, but he hasn't followed me back. He's not in the WhatsApp group yet or anything. I've spoken to some of them. More with Mbappe, who is on fire. With Vini too. I hope they keep scoring their goals here and then with Madrid too. They're two incredible players. I hope we do good things with the boss and that he manages to get the best out of both of them. We've got a really strong squad."