you don't
need to change the CPU just to run the card, but i doubt that old 7th gen can provide enough frames to the card to maximize it's potential.
the power supply definitely needs to be upgraded though.
look up this particular card on the manufacturer's product page or on a retailer like Newegg.com and check the required wattage.
for some help picking a new PSU:
PSU Tier List 4.0 rev. 14.8 (outdated) Last Update: 12-07-2021 Legend : Gray - EoL/obsolete and/or otherwise not recommended for purchase. Green - small form-factor (gold and blue colors are disregarded due to scarcity of SFX PSUs) Gold - best units in the tier (includes requirements for blue...
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