Deload

Hey, still newbie here

I am doing a program for 5 weeks and it has 6th week as deload. Which i never done deload before. Now i saw an option to extend work out to any amount of weeks so my options are :

1. Finish 5 weeks U/L split workout and 6th week do a deload week, then start same 6 weeks workout again

2. Extend original workout to any amount of weeks and do deload on last week

3. Finish 5 weeks U/L split workout and 6th week do a deload week, make a new U/L split workout to change exercises/movement ( all app created btw )

And how important is deload? How often do you have to do it if any? I am only 2 month in gym properly, before done 9 month at home with DB/BB/KB only.

Thanks