Hi Lola, some great ideas there from @Belinda_Booker I would think about what is going to have broad appeal across your community. Something which appeals to all ages, backgrounds, abilities - even if some are participating and some are watching. Food and music always bring people together. You may want to think about a theme to base it around such as Royal wedding, Wimbledon, midsummer, Salford’s 250 listed buildings, history of Salford, urban zoo, etc.
Once you’ve got your event concept and plan together I think it would be worth investing time in talking to local businesses and community organisations to get involved. Once you’ve got a few of them on board and mobilised you’re well on your way to a successful event! Good luck!