Have a look at Katrina Chambers on Instagram. She has a tutorial.

They look like they need the paint cleaned off to me?

Thanks for the replies.

I'm definitely no expert, but by trying to remove that paint wouldn't i be risking to damage those frames, especially in the corners?

Contact the window manufacturer for advice on what product/technique is safe to use.

Do you want the metal frames a different colour or do you just want them to not have over paint on them? Anybody who did that messy a job probably used a water based paint rather than an enamel. You could try scrubbing the metal frames with a slight abrasive cleaner and scourer. Test in an inconspicuous spot as it will take the shine off the metal.

If you want to change the colour I think you still need to remove the existing paint patches to avoid a lumpy appearance. I wonder about ongoing maintenance too, whereas the metal frames don't typically need maintenance.

Thanks for the replies.

Yeah I just would like to remove that messy paint job, I don't expect those frames to be shiny at the end is an old unit block and those frames have been there probably for a few decades.

I just want to make it look better and not messy, I guess I can try first to remove the patches as @bigreader mentioned or go the next level as it is explained here https://homeguides.sfgate.com/paint-off-old-aluminum-window-frames-80826.html.

I guess only after and if it sill doesn't look good I could try to spray paint it.

Sounds like a plan. Good luck.