Help Deciding Whether or Not to Upgrade

I’m mainly looking at upgrading my graphics at the moment, but I’m unsure if I should just update the card or if I need to update the mobo and all and do a fresh build. This is my first self built pc, so I’m not sure how it all goes.

Current graphics is a 3060TI and I’m looking at getting an RX 9070

Mobo: MSI B450 Tomahawk MAX II AM4

CPU: Ryzen 7 3700X 8Core 3.6GHz

64gb of DDR4 RAM total

I was considering getting the 9070 and updating to Windows 11 just not sure how going all new with only 1 component would be on this build. Do new CPUs fit into older Mobos? I know I can’t do new RAM and RAM is essentially the reason I’m not doing a whole new build in the first place lol.