I'm sorry your first job ended up like this. Things like this early in your career can really shake you for awhile, so I urge you to be gentle with yourself. There's no justifiable reason for speaking to you like you say she did. Yes, micropipetting is key, but just doing a few exercises isn't going to teach you muscle memory for it. That just takes time.
Since it sounds like you don't have as much bench experience as you'd like, I recommend this book: https://www.amazon.com/At-Bench-Laboratory-Navigator-Updated/dp/0879697083/ref=sr_1_2?dchild=1&keywords=at+the+bench&qid=1596046269&sr=8-2
It really helped me with some of my molecular work and how to operate in a wet lab.
I like At the Bench, A Laboratory Navigator by Kathy Barker and had a copy for years.
It will be missing some if the newer techniques, obviously, but has a lot of mol bio basics and great 'be a good scientist' advice.
For the lab sciences, I recommend At the Bench: A Laboratory Navigator. It's good good sections on everything from how an academic lab works to planning out your path through grad school to interpersonal issues and then some short summaries of (mostly biological) techniques you might encounter.
https://www.amazon.com/At-Bench-Laboratory-Navigator-Updated/dp/0879697083#reader_0879697083
It's a bit outdated at this point (2012) but still very valid. I tend to gift copies to students when they graduate and are going off to grad school, and they've mostly all said they found it really useful.
My molecular biology lab in 2013 had us buy this book
At the Bench: A Laboratory Navigator, Updated Edition https://www.amazon.com/dp/0879697083/ref=cm_sw_r_cp_api_i_IRZpFbQ8N2XZE
It has diagrams and a lot of helpful stuff for this :)
Give this book a read it goes over a lot of basic lab info
https://www.amazon.com/At-Bench-Laboratory-Navigator-Updated/dp/0879697083