Developers, programmers new to bitcoin engineering ecosystem Any sites, forums dedicated  to developers new to bitcoin.
Any recommended git repo, site that shows how to interact with a node, do .i.e. p2sh,p2pkh on testnet.
Any sites, forums dedicated to developers new to bitcoin

https://bitcoin.stackexchange.com
And if you your question is closed here then, https://reddit.com/r/bitcoin
IRC: #bitcoin-core-pr-reviews IRC channel on freenode
Slack: https://bitcoincore.slack.com, https://lightningdevkit.slack.com, https://lightningcommunity.slack.com and https://suredbits.slack.com
Follow bitcoin devs on Twitter
Sometimes you find or discuss interesting things on different GitHub repositories as well like https://github.com/bitcoin/bitcoin

Any recommended git repo, site that shows how to interact with a node, do .i.e. p2sh,p2pkh on testnet.

https://github.com/BlockchainCommons/Learning-Bitcoin-from-the-Command-Line