What do you think about the possibility of improving your calculations speed in mathematics? Do you think that it is possible, or do you think that it is an inborn skill such as intelligence.

I can understand math quite well, but I am horrible at doing calculations. Whenever I attempt to do any sort of calculation at all, my mind almost shuts off and it is very mentally taxing for me to do them. Since about middle school, I have always used a calculator because of my laziness towards/inability to efficiently do problems in my head.

I also have a friend who can preform math problems in his head very easily. He multiplies and divides 3 digit numbers in his head faster than I can type them on a calculator. According to him, it is easy and does not require any more effort than normal thought.

As I move into higher-level math, I am becoming really interested in improving my speed of calculations to a higher level, but I am unsure if it is possible. When I search it on google, I only get results about mental math tricks, but I want to be able to do the actual operations faster and without becoming mentally tired afterwards.