Hi jakub.grela325233wg, welcome to Thunkable!
Be sure to check out How to ask Great Questions v2.0, the Community Guidelines, and our Getting Started Guide to make the best of your Thunkable Community experience!
We need more information to be able to help you. Please check out our Community Guidelines linked above. In general, videos need to be in the correct format to be played, using the Video component. The Video component will already have the controls in it so there are no blocks to add for playing or pausing the video.