There are many ways to make it.
Some of them are
23*1=91 -- 2+3*1=5
---> 1 move to make 9 as 5.
2 moves to make 1 as + sign.
23*1=91 -- 3*3*1=9
---> 1 move to make 2 as 3.
2 moves to make 1 as * sign.
23*1=91 -- 23/1≠91
---> 1 move to make not equal.
23*1=91 -- 23*1<91
--- 2 moves to make greater sign from equal sign.
