Need a little advice.

I'm planing on buying a RTX 3060ti or 3070 and start mining. Right now I have a TT Smart 530W 80+ Bronze PSU and plan on mining for a single GPU right now with changing PSU. I can get Zotac Twin Fan 3070 GPU, costs around $950-1000. Is it worth it? Or How long it would take to break through? I'm relatively new so please pardon my ignorance. Thank you so much.

P.S. And should I go for an LHR? They are quite cheaper from what I can understand.