Screen sharing accompanied with camera and audio can be quite demanding for some computers. You can do a few things if your computer feels slower than usual:
- Close any unnecessary software.
- Avoid having more than a couple browser tabs open.
- On Windows, go to Task Manager > More details and, if your CPU is high, check which application(s) is consuming a lot and, if possible, close them.
- Restart your computer.
- Scan your computer for viruses.
If your computer's performance is fine, it could be that the issue is with your internet connection.