How many players can my MC server hold

I have an economy server with rtp crystalpvp plugins shop auction etc and the hosting wont allow me to upgrade to 16gb because its not available How many players can this hold:

CPU: 300%

NVME Storage: 180GB

RAM: 12GB

Server: Dedicated Ryzen9 3950x

My goal is to hold 60-70 at once at the release so im not sure what I should upgrade to for this.