In short, yes: but the precise rules depend both on the university you'd like to connect with, and also on the laws of your country.
What you should know
Unibuddy’s Terms of Use require users to be above the age of digital consent in their jurisdiction, and you may need to provide your date of birth for verification.
Some universities do choose to restrict use to those aged 16 and over.
If the university you'd like to connect with has such a restriction in place and you are younger, you should contact them directly to ask about alternative ways to engage or access information.
Why do I have to be above the age of digital consent? I just want to chat with an Ambassador!
Under GDPR Article 8, a child must be at least 16 years old to give valid consent for services offering personal data processing. If someone is younger than this, parental or guardian consent is required - unless national law permits a lower age (between 13 and 16) for that country. You can read more on this here.
Because different countries have adopted different thresholds, the age at which someone can freely use an online service like Unibuddy (without parental consent) varies by country. Always check your national data protection law or your university’s guidance to understand the rules that apply to you.