Im looking to add a Sidebar to my HomePage

hi Im looking to add a sidebar to my homepage where I can show content.
I have a lot of free space on the sides and would like a sidebar on the homepage and also all of my pages.

I have a WordPress website called https://Www.StockPicksNYC.com

Its a “Shell Lite”Theme
I really don’t want to switch my theme. i really like it.
Im tried a few plugins but no luck. If you know of any plug ins that would solve my issue I would appreciate it.

i have have to do some css or php HTML and that’s OK too. step by step instructions would help. I’m a beginner but a quick learner. I built my website from scratch.

I just need a little help here. The sidebar is a must , and I am stuck.
Thanks