@Sh ***
You would need to leave the country and come back, and whether you get a visa on arrival or visa exemption depends on your passport. Different countries get different things. UK gets a visa exemption, for example.
Some people just cross the border and come straight back. But you can only do that two times per year, and if you look like you're abusing tourist visas / visa exemptions / visas on arrival, immigration officers might question you. But if you've not been here long I don't think it matters so much