We do not have Sony Spresense Arduino examples at this time. However, here are a couple of options that we recommend to get started with the Spresense:
Install the Spresense Arduino library (Spresense Arduino Library Getting Started Guide). Re-write the Arduino Nano 33 BLE examples to work for the Spresense. This generally means you will need to #include the downloaded library, fill a buffer with image data, and call run_classifier().
Install and use the Sony Spresense SDK (Spresense SDK Getting Started Guide (CLI)) without Arduino. Here are some examples to get you started using Edge Impulse with the Spresense SDK: