Okay....
First off, welcome
Second...
Open Sesame is part of a 3 part dry/soluble "finishing trio" along with Beastie Bloomz and Cha Ching.
Open Sesame is intended to be used (in Autos) generally at the transition from veg to flower and
it's purpose is to increase the number of bud sites....which isn't, actually, always a good thing.
If you have too many bud sites then the available energy for flowering can be divided amongst
too many recipients and then you run into small buds and too much bushiness (and a tough trim/harvest)
They (the finishing trio) aren't really to be considered "foundational" or "main" nutrients.
You need a veg nutrient that is Nitrogen appropriate for the vegetative stage and you need a bloom
nutrient that is P & K appropriate, and maybe a "base feed"...Big Bloom is a good example of
a base feed....earthworm castings, bat guano..etc. (I know, it's counter-intuitive since the word "Bloom"
is in the name....it's not a bloom nute (at least specifically)
Happy Frog has a precharge of nutrients, but it only really lasts 2 weeks at best in my experience.

OF (Ocean Forest) lasts longer BUT is generally considered to "hot" (too MUCH nute precharge)
to start autos in.
While I am using them right now, I don't particularly recommend Fox Farms Synthetic nutrients...
they work, they're just sort of a hassle and they aren't organic. BUT, the examples of what I'm
talking about in that line-up are Grow Big (Veg nute) and Tiger Bloom (Bloom nute)
Also, autoflowering cannabis can't handle the same feeding schedule as photoperiod plants and
the feed schedules are designed for photos...with autos, it's a good idea to start at 1/4 strength
and work up a bit to half or maybe just above that...while looking for nute burn on the tips of
the leaves.
Cheers!