Use ordinary PLA for the first A1 print. It removes enclosure temperature and flexible-filament feeding from the diagnosis, which is exactly what you want when the printer is new.
Load a dry spool, select the matching material type and let the A1 purge until the new color flows cleanly. Remove the cooled purge strand with tweezers only when the toolhead has stopped. Never reach around a moving or hot nozzle.
Choose a short model supplied by Bambu or a simple calibration model in Bambu Studio. Confirm three details on the print screen: the printer is A1, the plate type matches the installed sheet, and the filament preset matches the spool. Leave bed leveling enabled for this first job. Flow dynamics calibration is also sensible when the printer requests it for a new spool.
Watch the first layer. Lines should touch and look even across the part. Separate round strands point to too much nozzle gap or contamination. A rough surface with plastic pushed sideways suggests too little gap. The A1 normally handles Z positioning automatically, so do not start changing hidden offsets. Stop the print, clean and reseat the plate, inspect the nozzle for residue, then repeat calibration if the first layer is clearly wrong.
Let the plate cool before removing the model. Flex the removable sheet rather than prying against the bed while it is mounted. A successful first print should release cleanly, show continuous lower lines and have no layer shift or scraping marks.
Save the exact project and filament preset. It becomes a useful known-good comparison when a later custom model fails.
If the first layer looked uneven or the print did not release cleanly, it is worth revisiting the initial A1 setup steps before blaming the model itself. The A1’s calibration routines are also worth understanding once you move past this first controlled run, so you know which test to rerun and when. For the habits that carry over to any new printer, see the general beginner checklist.