And if you want to use service principal authentication (assuming you have already one) then you need to add this servicep principal to fabric workspace (like in url you send :How to use service principal authentication to access Microsoft Fabric's OneLake (dataroots.io)).
Then you can use service principal authentication in following way in databricks:

storage_account = "<storage_account>"
tenant_id = "<tenant_id>"
service_principal_id = "<service_principal_id>"
service_principal_password = "<service_principal_password>"

spark.conf.set(f"fs.azure.account.auth.type.{storage_account}.dfs.core.windows.net", "OAuth")
spark.conf.set(f"fs.azure.account.oauth.provider.type.{storage_account}.dfs.core.windows.net",  "org.apache.hadoop.fs.azurebfs.oauth2.ClientCredsTokenProvider")
spark.conf.set(f"fs.azure.account.oauth2.client.id.{storage_account}.dfs.core.windows.net", service_principal_id)
spark.conf.set(f"fs.azure.account.oauth2.client.secret.{storage_account}.dfs.core.windows.net", service_principal_password)
spark.conf.set(f"fs.azure.account.oauth2.client.endpoint.{storage_account}.dfs.core.windows.net", f"https://login.microsoftonline.com/{tenant_id}/oauth2/token")

# read with spn
df = spark.read.format("parquet").load(f"abfss://default@{storage_account}.dfs.core.windows.net/data/unmanaged/t_unmanag_parquet")
df.show(10)

# write
df.write.format("delta").mode("overwrite").save(f"abfss://default@{storage_account}.dfs.core.windows.net/data/unmanaged/fab_unmanag_delta_spn")