What grade motor oil goes in a 1972 suzuki ts250 also how do i check the level so i don't over fill it?

The TS250 is a 2cycle engine and as such the oil is mixed with the fuel. Use only 2 cycle oil and mix it according to the manufactures recommendations unless it has a oil resivoir that automatically mixes the oil for you. In that case just fill the resivoir to the top. You cannot overfill it.