Learning the Program
How do you remove a note from a measure with getting rest? How do you connect the notes? Can you move from right to left and left to right rather than moving up or down? How do you create a measure by adding a bar line. How do you encase 2 notes within vertical lines. The instructions on this program are not good.
Comments
Which instructions have you looked at? Have you looked here https://musescore.org/en/handbook/4
If you delete delete a note using plain Delete you are removing sound and so you leave silence of the same duration, i.e. rest, in its place. This keeps the correct number of beats in the measure. If you really want to also reduce the duration of the measure you can use CTRL+Delete but you really only should need to do that in special circumstances -e.g. to create a pick up measure.
It is not clear what you mean by "connect notes". To connect with a slur, select the first note and use keyboard shortcut S. You can then extend it to cover more notes with SHIFT+Right arrow. To connect with a tie, during note input, enter the first nite, then select the duration of the next note and use Keyboard shortcut T. That will enter the tied to note and the tie. To connect notes with a beam use the beam properties in the palette. See https://musescore.org/en/handbook/4/beams for more detail.
To move notes left and right select the notes you want to move, use keyboard shortcut CTRL+X to cut, select the point you want to move them to and paste them using keyboard shortcut CTRL+V. See
https://musescore.org/en/handbook/4/copy-and-paste for more detail.
To add further measures go to the Add menu. See https://musescore.org/en/handbook/4/adding-and-removing-measures for more detail.
It us not clear what you mean by "encase teo notes in vertical lines. Please explain in more detail what you are trying to achieve. A picture, even hand drawn may help.
If you need further help on these topics, please come back, but it is best to have one question per thread as otherwise sorting out which answer goes with which question gets difficult, so I recommend starting a new thread for each topic.
Here is a "getting started" tutorial I created that should answer many of your questions:
https://www.youtube.com/watch?v=dIMFQ7s31DM
If you continue to have trouble after watching this and reading the other responses here, please explain your questions in more detail.