Automated and Manual bots
There are certainly automated bots which can backlink you free only from 100 sites and they would create 1,000 backlinks for a premium account which was registered with them but you might be penalized by search console and you wouldn’t like it.
Manual backlinking is the best backlinking so far which makes the spider to crawl you to the first page, manual backlinking are backlinks created from your competitors.
Note: Avoid bots and face manual.
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