Hello! I’ve been looking for an upgrade from a 450 watt power supply, and I’d like to future proof for a possible 3080 card. Any suggestions?

I prefer to use an 850W PSU for RTX 3080

Get a 850w

I will also recommend 850-1000w Gold or better for 2080ti or 30xx GPUs.
Especially if you overclock the CPU and GPU.
Also most importantly use the power cord and all the wires that comes with the new PSU
I got lazy and did not change the power core to the wall outlet and was having random reboots under load.
Troubleshooting the issue I happened to feel the cord from the wall was very warm at the PSU
Wire was 18ga on the old PSU and the new wire was 14ga and made a world of difference.
Not hot anymore and no more random reboots.
 
EDIT: Also if you do not change out all the cables you can burn up hard drives and other peripherals. 

850W is enough but if your budget does not restrict you get 1000W.  The nice thing about having a larger PSU is that it remains cool most of the time with light load.  Go with titanium or platinum if you often leave your PC ON most of the time and/or your PC is a multi-purpose system (gaming, file server or plex server, etc).  As what they said, use the power cord that comes with your PSU.  

I think that everyone here is spot on by saying an 850W or above. However, there are some other considerations:
 
You stated you want to future proof, 850W is putting yourself pretty much right at the top (with a little breathing room) of where you will currently be. If you add another card, or additional components, 850W may not even be enough. That being said, a 1,000 watt PSU is probably where you want to be. Just enough that there's plenty of breathing room, but still affordable. The 3080 is a monster of a card and although 750W is plenty to run it, it's always good to have room for more. Also, these EVGA PSU's are absolutely bulletproof and will last quite a while. May as well go higher and enjoy the peace of mind.