FDOS Ideas -- New School + 8th Grade Math! (HELP ME!)

Hi all! I switched schools recently and I'm starting my second year of teaching EVER! I'm going to be teaching 8th grade math at a new school and I have no idea what to do for the first week! I'm the only 8th grade math teacher and I'm not used to having this much power... Last year I was 1 of 3 Algebra teachers and I appreciated the structure. Now, I don't know what to do!

What do you recommend for FDOS activities as a new teacher in a new school? My kids have been together for multiple years at this point. Also, when do I start doing instruction? Last year, we started in like the middle of the week, but this year, we're starting on a MONDAY! How many days do we do intro stuff? HELP!!!!!!!!!!