Using cdn for auto feed website

Hello guys. I have a wordress website that using echo rss feed plugin to publish posts automaticlly from another feeds. So the problem start from last week when the database storage got heavier than before and website will down every time I active auto feed plugin. I have tested all cache plugin but the problem is still remain. object cache database can not work correctly and etc…
So I decide to use cdn from Cloudflare but I want to know does it useful for my website to stop downing the server?
my server has 24 gb ram and 12 core cpu

Do you use any WordPress plugins for cache?

What kind of “cache” options have you got enabled in Cloudflare?

Moreover, are you using any Page Rules for specific URL for your RSS feeds to bypass cache or some other as far as Cloudflare does not cache the HTML documents by standard option, can you check that out and write back with some feedback information?

Thank you for answer. I have checked almost all good cache plugin including litespeed cache for a while and also wp rocket even wp3 and hummbrid
But after I change vps to dedicate server I found out using cache just make it worse and I decided to deactivate all of them and just using cloudflare.
This morning the main problem happened again and website got suspend because of more using resources. I can not optimize database including wp_posts and wp_post_meta because of too many data and also I don’t know how config a cache plugin professionally maybe someone can do it…

I don’t have any page rules in cloudflare
what should I do for it?