With a background from the metal industry as a sheet metal worker and exchange studies at the School of Visual Arts in New York, Andreassen graduated from the Oslo National Academy of the Arts with an MFA in medium- and material-based art in 2019. He received the Norske Kunsthåndverkeres Student Award for his Master project «Ringvirkninger « and in 2020 he was awarded a 3-year working grant for newly established artists from the Norwegian Cultural Council.

Andreassen has shown works at several fairs and galleries both nationally and internationally, such as CHART Art Fair Copenhagen, Norwegian Sculptors' Association Oslo, London Design Fair, Gallery KÖSK Oslo, BOON Paris, Gallery Format Oslo and Officine Saffi Milano where he was nominated for Office Saffi Awards 4 and was awarded the residency award where Päivi Rintaniemi will host his residency in Seinäjoki (Finland) 2022.

His work has been acquired by the Norwegian National Museum's collection and by several private collectors.