i had to pick green tomatoes because the plant had blight how do i ripen them

welcome to GoY
on a warm window sill or in a paper bag with something like a ripe banana. back end of the season you can put them in a drawer to ripen too.

If you have loads, try making green tomato jam or chutney - both taste great! Just google it and the recipes are all there. To anyone else with a glut of homegrown fruit and veg try this site, www.allotment.org.uk. The recipe section is great.