If you would consider it, buy a whole new system, prebuilt. You are running a very old platform, and your PSU may be running the risk of failing soon, especially if it is a lower quality model. I am all for building a computer yourself, I have done it personally, and helped friends do the same. However, right now, the GPU market is too wild. Prebuilt manufacturers can actually get their hands on GPUs, and have entire, complete, PCs for not much more than some scalpers want for the GPU alone sometimes. You do need to make sure you get a good quality prebuilt, that uses quality components, but it is a route I would suggest you look into.
As for your question, an RTX 3060 ti would work without issue in that system. The only real constraint is your PSU. It needs to be strong enough, both in wattage, and in quality to be able to take a stronger GPU in the current build. You may also run into issues where your CPU will struggle to keep up with what the GPU can do, but this is not an actual problem, just a balance issue with the PC, as long as your CPU can stay cool enough under high load. I know the FX series are very power hungry, and need some very good cooling.