I did mine for 5 years in april.
didnt book. walk in. But i watched the 1 hour video online and kept the QR code it gave me.
went there at 7.30 they started to take in people who has bookings. So i would say i waited around 2 hours for my turn. When you enter the door tell or show the QR code to the lady sitting on the right (giving queue numbers) that means you watched the video. So they will give you a different queue number (i think white color) to skip watching the video. they will take i think 550 or 505 baht. cannot remember. i waited my turn probably another 30-40min. Did 3 tests about color, reflects, eyes. Took my photo and waited another 20min. All done
so no need booking but if not you will wait probably 3-4 hours to do all. went there 7.30 done around 11:45
video you need to watch:
https://www.dlt.go.th/en/renew-license/
https://www.dlt-elearning.com/forignerhome
you can find it in here but you need to register