Hi @hotflamingpanda
The laptop supports up to 8GB of DDR3L 1600MHz (PC3L-12800) SODIMM ram in 1 slot, i.e. 2GB, 4GB or 8GB
Here’s the [http://h10032.www1.hp.com/ctg/Manual/c04409502|maintenance and service guide] for the laptop, taken from this [https://support.hp.com/us-en/product/hp-15-r000-notebook-pc-series/6875200/model/7124130/manuals?sku=G9D66UA|webpage].
Go to p.76 to view the necessary pre-requisite steps and then the procedure to remove/replace the ram module. At the top of p.76 you will also find the part numbers for the different capacity modules. If you search online using the part number ''only'' you’ll get results for suppliers.
The hardware manual only shows how to replace the one module, indicating that there is only 1 slot. This is confirmed by this [https://www.crucial.com/compatible-upgrade-for/hp---compaq/hp-15-r011dx|supplier] which also shows that the laptop model only supports up to 8GB in 1 slot.