You can find care instructions for your specific Blåhaj on the IKEA website under “Product Details”, though their wording differs by region. A sample:

Care: Machine wash, warm (max 40°C), durable-press cycle. Do not bleach. Tumble dry, low temperature (max 60°C), normal cycle. Do not iron. Do not dry clean.

Some owners report preferring a gentle wash cycle and/or air-drying on a drying rack.

Regardless of which approach you take, Blåhaj may require some fluffing afterwards.

Yeah machine wash up to 40 with a mild detergent

https://www.ikea.com/gb/en/p/blahaj-soft-toy-shark-30373588/#