Can a bolwer bolw underarm during a cricket match?

No, there is a very famous moment in cricket history labelled 'the most unsporting moment in sports histroy' in which, during the final match of an ODI series between Australia and New Zealand, Australia's Greg Chappell was bowling the final ball of the match with the Kiwis needing 6 runs to win and he bowled it underarm, so that it was impossible to hit for six. After this the underarm bowl was made illegal.