Hello @Max
Halo is not a product supported in this forum. You should file a support query directly to the software manufacturer Forums or Support. Try searching online for HOW TO SUBMIT A HALO SUPPORT TICKET.
In advance, I can share as some personal knowledge that Halo Infinite will require full Direct X12, while your card feature level is DirectX11. That means that some titles using DX12 may work, but for some specific technologies in DX12, it will not.
Another option would be to consult in the GPU manufacturer forums, if there is any Driver update or feature update planned for your Graphics card.
About using a eGPU, there are options such as GPU external enclosures, where you can connect your usual GPU card to a case with it's own power supply, cooling, etc.
Hope this helps with your query,
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