Thanks for the details. I'm not much of a gamer anymore even if I still build & spec high end Gamer Boxes for my son and nephews respectively. One of my nephews is a Software Engineer for EA Sports here in Metro Vancouver, and the other has a degree in Computer Science and does programming. And yes, my son gets EA Games for his birthday, and Christmas from them.
DisplayPort & HDMI Specs and capabilities have been leapfrogging each other for some time. Both carry Video and Audio in the same cable. The limitation of this computer for HTPC and Gaming use will vary based on it's optional Graphics Card and if it is Display Port 1.4 or 1.2. I cannot tell for certain if this has the optional Discreet Graphics Card mentioned in the Specification as the Ad posted doesn't tell me much. Can you ask the seller to give you full details so we can get this sorted?
DisplayPort 1.4 has a maximum total bandwidth of 32.4Gbps and a maximum total data rate of 25.92 Gbps. This is about the same as HDMI 2.1 That gives it enough bandwidth to handle a 4K UHD stream at up to 120Hz with 24-bit/px color, or a 5K display at up to 60Hz, with 30-bit/px color. It even supports 8K video, but only at up to 30Hz due to the hefty bandwidth demands. The DisplayPort 1.2 standards had a maximum sample rate of 768 kHz, a maximum sample size of 24 bits, and a maximum of eight audio channels. It's similar to HDMI 2.0
According to PC Gamer in 2018
AMD'S RYZEN 5 2400G IS A GOOD OPTION FOR A BUDGET GAMING PC
It also states: "As a home theater PC (HTPC), the new Ryzen APUs deliver an awesome value and a great experience. AMD's drivers have full support for all the common video formats"
Remember that this PC was released in 2018 and if it doesn't have the optional video card the comments in the review above will stand.
Here is AMD's page for reference on the integrated graphics and CPU:
AMD Ryzen™ 5 2400GE with Radeon™ RX Vega 11 Graphics
Please advise the model for the TV and Soundbar so I can see what connections would work best for you. But I'm thinking at $300 (or less if you can negotiate it down a bit) it would make a nice HTPC with modest Gaming capability. If it has the Optional Graphics Card, even better.
I hope this is helpful.