You totally can. Agile is more about having a growth mindset than 'doing scrum'.

A small subset of it is to manage stakeholders. Otherwise they will say ‘build this blob of an idea’, and will not value incremental additions towards the final version that can give a lot of direction on what’s doable/not necessary/necessary. They will also be majorly disappointed if one day they expect the blob of an idea to magically appear, as it won’t meet any expectations.