Myfitnesspal’s database is surprisingly good. Most chains are in there.

For other restaurants I guesstimate. After 5 years my guesstimates have gotten pretty accurate.

I also don’t sweat about perfect tracking. It’s more about observing general trends. 100 cals up or down all averages out over your lifetime. Or even a single week.

That said when you have strict goals, the only solution is not to eat out or at least to limit it a lot. Like when you have to be a certain weight or bodyfat for a specific event that’s X days/weeks out