how can Knew the bad boot

hello
The average visitor stay on my site has decreased from 2 minutes to 8 seconds, what should I do?
this is a boot list
what should I block and how, please help me

Most of these bots firstly look into the robots.txt file, and if you tell them not to scrape your website they won't.

But most of these bots are good, they add your site to search results, etc...

For bad bots protection aka custom made scripts that scrape website content,
Cloudflare paid plan, Datadome, etc ...

But this is a cat and mouse game because scrapper writers are finding ways to bypass these protections.

100% way to disable scrappers is to:

#1 Disable your site for all visitors

#2 Add some sort of registration or paywall and kick accounts that have red flags: too many pages visit per day,
on multiple pages leaving them in a short time, etc... But this also can be bypassed with a list of accounts, a list of proxies, and
if each bot behaves more human-like without triggering any flags.

As I said cat and mouse game. Prevention is possible to a certain level.