Many subreddits are fine with posting a link to your own content, as long as you observe the 10% rule mentioned in the Reddit wiki: for every one link to your own content, you should be posting 9 links to content you are not affiliated with. You should also be participating in the discussions on the subreddit instead of just linking and running.

When you see how many e.g. travel subs have been overrun with links to people’s own YouTube channels, so they can pursue the dream of being influencers, it is easy to understand why there is little patience for flagrant self-promotion.