Building a close friendship with a guy while making your platonic intentions clear is absolutely possible. The key is open, direct communication from the start. Freely use the word “friend” when talking about him and your relationship. If he starts crossing lines into flirty or romantic territory, kindly but firmly redirect him back to friendship.
It may feel a bit awkward at first, but setting those boundaries early saves a lot of potential hurt and confusion down the line. A true friend will respect your feelings. Stay consistent and things should fall into a comfortable, rewarding friendship. Wishing you all the best as you navigate this!