Can i use a dash in a sentence like "going to a room - cant remember where this took place"

No.

Explanation:

Dashes are used to replace a parentheses or a colon. They can also be used to censor words and are often used to tell a range between numbers like 19-21.

In this case, you’re trying to use a dash to denote a connection which a dash can be used for but only when you’re connecting two words that are already have hyphens or are being used as a modifier.

look it up

Explanation:

spiderman is cool and epic

the cost of attendance or coa is an approximate budget for the cost of attendance of the whole academic year. in order to calculate this, universities take into consideration many factors like room and board, tuitions and fees, books, transportation and personal expenses such as medicine, laundry, clothing. all these factors combined make up the final sum to the cost of attendance in each university.