Laptop too weak for discord and games?

I often play video games with my friends. The only problem I have is that with larger and more complex games, I don't hear my friends and they don't hear me.

Is it because of the performance of my laptop or the internet. I don't have a bad laptop either

Neither nor. That should be a software problem.

are there similar problems under Teamspeak? If so, it is due to the microphone or its processing. If not, it's up to Discord.

May be. You can turn off hardware acceleration in Discord under Settings under Appearance. This helps when Discord is drawing too much power.