Can I get friends as a 23 yo in university?

Hi!
When I'm 23 year old I'll be going to be an undergraduate in Japan.
I know most of my classmates will be around 19 and I know in Japan age is a thing.
So is there any possibility for me to be friends with my classmates?
Will they see me so super old that I can't hang out with them and join the clubs and such?

Sorry if it's weird question but I'm otherwise sure to study in Japan but this concerns me, I don't want to be alone..

19 yo and 23 yo are both young adults and not that different - not different like 12 yo vs. 16 yo.
Besides, there are lots of students in their 20's, as some Japanese students who did not get accepted at school of their choice keep trying every year until they get accepted.

Well, to be honest, 23yo freshmen are a rarity in Japan. But, yes, you can hang out, naturally. I've seen it happen, in Japan. But you know what? The person kept the age a secret for just a couple of months so that students won't judge the person by the age. Also, in Japan there is the senpai/kohai culture. It will be a great advantage if you can be sure to use keigo to those who have been there longer than you.

Yeah, you better be on your best behaviour around senpai, otherwise they may think it's a-ok to punch you in the face and stomach like this one. https://mainichi.jp/english/articles/20180112/p2a/00m/0sp/024000c

in Japan there is the senpai/kohai culture.
is still there ?
it may there in unsophisticated athletic clubs in a second or lower levels of universities.
if you go to good universities, almost none.

even if senpai/kohai is not there, age difference is another barrier between you and other students.
you will be treated as a guest all the time. if you bear this situation (maybe for a year), they may treat you as a member. (sometimes, it may be easier for you that you stay in "guest" situation.)

Serious this kind of questions and answers are really awkward.
Making friends is pending on your behavior

I was 25years when I entered japanese College. It was easy for me to find friends, but I didnt really liked to hang out with them in my free time, because well they were like little kids to me! I prefered meeting my own friends around my age from outside the college. But inside college I studied together with them and also lunch time etc I spent with my classmates! No problem at all ;)

Glad to know that there's some change to get friends in there. ^^
And about the member and quest kind of attitude, that's fine.
I'm from Finland and that's bit similar.. We also have that 'inner' and 'outer' circle of friendship and getting to the inner circle takes.. Lots of time.
So taking effort, all good!
The age was just something which made me worried. Like, if trying to join a club and they are like ehh you're too old and then they ignore me or something.
I was bullied in school so my weird thoughts might come from there. Sorry '*-*

Just to clarify about the senpai/kohai thing, it's not as strict as it is in athletic groups, and it never was, but of course it still exists! And it's not even a big deal. The majority of teens and older commonly use keigo to students who have been in that school or group longer than them. The relationship will be quite equal between each other, but just a little keigo makes a great difference, even though most senpais tell you it's okay to use "tame-guchi". Just laying out facts.