What is gauge reading in lo and high side pressure when using r 410

There is no specific reading on the high and low side since it changes rapidly depending upon a specific set of conditions and those conditions are what causes the reading as you call it to change. When people ask this kind of question it is usually because they are doing something they should not be doing. If you really want to know about the refrigerant cycle I suggest signing up for a class at your local educational office since this venue cannot possibly explain all you need to know and anyone who says different has no idea what they are really talking about.