Also can this aid cover 100% of all spendings?
International students at BU are NOT eligible for need based aid as stated on their website. International students are eligible for merit aid which has a $25,000 maximum unless you receive the full tuition Trustees scholarship. For the Trustees you would have to be in the top 1-2% of admitted students. Even then you would have to pay room and board which is over $15,000/year.