Hi,
Here's the [http://h10032.www1.hp.com/ctg/Manual/c06248419.pdf|maintenance and service guide], taken from this support [https://support.hp.com/us-en/product/hp-pavilion-15-cs0000-laptop-pc/20284004/model/21837063/manuals|webpage], for the laptop.
Go to p.37 to view the ''necessary pre-requisite steps'' and then the procedure to remove/replace the battery.
At the top of the page you will find the HP part numbers for the available batteries. Search online using the ''part number only'' to find suppliers that suit you best.
Try creating a [https://www.lifewire.com/how-to-generate-windows-10-battery-report-4587396|battery report] to check the status of the battery, before replacing it to see if it is the problem. Check the Design Capacity versus the Full Charge capacity.