creepy boy or not?

ok so please read this so i can get input. i go i to a lot of detail so your getting it exactly how it is. i’m a freshman right. so i found a girl to sit with at lunch who was alone too so now we sit together. this boy came up to the table one day (let me note he’s super friendly and talkative and just easy to talk too like holding a conversation(also noting i think he’s a sophomore but could be a junior)) and we found out we had history together so he got my name and he came up and talked to us for a week or two (this was the beginning of the school year) and about a week ago he stopped showing up. some days he would say hi to me in history or wave but that was about it. it’s been about three days that he has said hi to me every day and talked to me a bit. wether it was at the end of class or in the hall we had a small conversation. so at the very end of the school day we have different clubs to pick from every day. a popular one is swimming and everyone wants to do it because it just got added. so he was telling me i should join the swimming and i was like i want to but i don’t have a swimsuit and i said i’ll try to get one tonight maybe and he said i’ll buy you one and i took it as a joke and said ok jokingly (he jokes a lot so i wasn’t surprised) then i forget what kinda happened but he said a bit later come do the swimming just get a suit there and i was like they said i had to bring my own and he was like for real and we talked really quick how you needed your own stuff. anyway he then said i can just get you a suit from like target and i was like i don’t even know my size and he said how about i just take you to target and you get one. so i wasn’t really thinking but i was just like actually like trying to confirm if he was being legit. i guess he was and i was like ok put your number in my phone (not like my mom would let me go i wasn’t going to i had my excuse ready) and then he did and that was it. does anyone on here have a bf that can say if this was him trying to be nice or flirty or creepy or trying to take advantage of me since i’m a freshman? does anyone have any experience like this that can let me know? and what should i do?