Hood Hinge to firewall Rust, How to repair?

How would you body guys repair this?
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I want to learn how to weld. I saw a mig welder at harbor freight. would this get the job done?
any suggestions? Is this to small? ony using on sheet metal and for holes in engine bay.

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You could weld a patch over the weak area, grind it smooth, then finish it all off with a thin layer of body filler. Or make a relacement piece, trace it on the firewall, cut out the old and weld in the flush fit replacement piece and smooth with filler. Whatever you decide, it looks like it needs to be reinforced to hold the weight of the hood.