On our front lawn there are so many bald patches how can I fix it?

https://www.gardeningknowhow.com/lawn-care/lgen/brown-lawn-fixes.htm

I'm pretty sure that's caused by a underground grub or beetle. Take photos on your iphone or tablet & show a garden centre. The soil will need to be lifted up, loosened with a fork for drainage holes & airation. Replace with new soil after bug or grub treatment. Then you could place more grass seed & lightly water. Do you have a dog or children using the lawn area a lot? Maybe consider which is more important if so. Hard one if so. 😇

I moved into a home that the yard had been neglected for quite some time. I started by digging out, pulling as much of the weeds and roots out I could. Used Scotts Bonus S to kill what was left and save what grass there was. Aerated the yard, and by then it was looking desolate in places, splotchy in others. Used grass plugs, we used St Augustine as this the best grass for our area, dug a small hole, put in a small sprinkle of new grass fertilizer and plated the plugs, well spaced out. The yard looks wonderful, filled in nicely, very green and healthy. Good luck!

My best advice is to patch it. You can buy patch at garden centers. You might need a bag ot topsoil. Just rake the bare spots apply seed patch and topsoil if needed. And water often