Claiming ESA if left job?

The new style esa mentions that if you get a severe disability premium in another benign you can’t get new style esa. I get pip at standard rate which is due to end in a few months. I’m slightly confused by the disability premiums mentioned on the new style esa.
Also, on the esa guides on this forum mention that the esa claim form can be used to look at a pip claim again, as esa and pip now ask similar questions? I may have picked that up wron*, if,you could advise.

If you could advise thanks

I contacted ESA yesterday and tried to apply for new style ESA, here's how it went, advice please:
1.Asked me if I'd been to GP and had a sick note. I didn't think I'd need one, I thought I phoned them first. They asked me when I last worked which was mid Feb...and why I'd didn't apply from mid Feb
2. Asked what I'd been doing since then, I said doing training as part of a charity run scheme I'm involved in which has now stopped because of virus and applying for jobs
3. They said PIP is a sickness benefit and that I should apply for that- this seems incorrect.
4. They said I could apply for JSA - I pointed out that this isn't a disability related work benefit
5. I could apply for ESA because of my underlying conditions

Advisor said that if after the virus is over (who knows when that'll be) I would be able to resume my training - that's not going to get me a job is it!?...therefore ESA wouldn't apply to my situation.
I'm totally confused.... my last job was in mid Feb and I thought I'd have a job by now.. that's why I didn't apply for ESA. I did have a job lined up last week but it fell through because of virus.
Should I try and get a sick note and ring again? Totally confused!!

Sorry for the confusion...I was being provided training from a sight loss organisation on talking software...without this training being completed I won’t be able to work to the best of my ability.
My opportunity that I had been offered last week was through an employment agency and I was told by the employment agency that it fell through due to internal recruitment/virus. The agency was very vague as to why it had been pulled.

I would need to complete my talking software training to enable me to work to the best of my ability. I use accessible technology in terms of software and a large print keyboard, with the software I use it can take time to purchase it and download it onto the organisations IT systems,(sometimes months for a organisation to install software). I also need to complete my long cane mobility training .to enable me to get to work safely... which was stopped due to virus.

With JSA as far as I know means that I would have to be immediately available...but with the issues with software being installed on time in order for me to begin work immediately that wouldn’t be the case...for example I couldn’t walk into an office tomorrow and begin work without the use of my software.

Just so I understand how does the severe disability premium work with jsa? Can I apply for jsa? I’m confused by the criteria for jsa.