write table in lakehouse

Hi jcamilo1985  - Thanks for using Fabric Community,

As I understand you are very new to fabric and sparkR, would like to learn explore things on it. 
I am sharing few links that helps you get more insights with fabric and sparkR.

Fabric Link: It helps you understand these new resources (datamart, lakehouse, pipeline...)
Get started with Microsoft Fabric - Training | Microsoft Learn 

Spark R Link: helps to understand how to use SparkR
SparkR overview - Azure Databricks | Microsoft Learn
Tutorial: Work with SparkR SparkDataFrames on Databricks | Databricks on AWS

I was able to create a table in lakehouse using below code, attached screenshot for reference -

# tableName <- "<catalog-name>.<schema-name>.<table-name>"
tableName <- "gopi_lake_house.abc"

data   <- list(
            list(1L, "Raymond", "green",  "apple"),
            list(2L, "Loretta", "purple", "grape"),
            list(3L, "Wayne",   "yellow", "banana")
          )

schema <- structType(
            structField("id",    "integer"),
            structField("name",  "string"),
            structField("color", "string"),
            structField("fruit", "string")
          )

df <- createDataFrame(
        data   = data,
        schema = schema
      )

saveAsTable(
  df        = df,
  tableName = tableName
)

# Verify that the table was successfully saved by
# displaying the table's contents.
display(sql(paste0("SELECT * FROM ", tableName)))

 Hope this helps your query. Happy Learning.!