Suryanamaskar is a very good exercise that builds body flexibility as well as strength if required. It is also very effective in preventing and reversing Sarcopenia, which is aging related muscle loss.
One can do 4 rounds in one session per day to start with (best on empty stomach, like in the morning or an hour before lunch) and then add 2 further rounds every week. Going up to 10 rounds is good for building body flexibility. Going up to 20 repetitions and more, builds strength and muscles.
There is a breathing sequence that goes with every position and it is very simple to remember because it is natural. Whenever the abdomen or chest expands or stretches, breathe in and whenever the abdomen or chest contracts, breathe out.
But first, please cure any spine or slipped disc related problems as advised in my book “Become Healthy or Extinct”.