What do you wear on the beach when you go on holiday?
I use swim mask, boardshort and flip flops to go to the beach
Ok but don't need "am" ('m) here. You need a subject and a verb in an English sentence, I is your subject, use is your verb. You do not need "am" - a form of "to be" (another verb).
Also, the correct word it to go, not for go.
"I use swimming trunks and flip-flops to go to the beach" is correct.
two words are off 'use' and 'for'.