upgrading 3060 MT—advice appreciated

Hello, hoping y’all can help me out here. Bought a 3060 MT with 1tb M2 ssd i7 8th gen 32gb ddr4 ram for around 300 because ram prices are crazy and I could use a processor upgrade anyway. Was planning on moving my 500W psu and old graphics card (gtx 960) + 1tb ssd over from the old Inspiron I’ve had for 11 years but it looks like the psu is the wrong shape. I’m willing to spend another 100-200 if necessary (budget is tight). Do I need to buy a new psu or gpu? Or change the case?

The pc needs to handle moderate to heavy photoshop use (with pen display) in addition to general use and light gaming. If I’m missing something or off track let me know..

Thank you