Hi, @zabronix ,
First of all, there are excellent video tutorials at https://www.youtube.com/@algodevs
Please go to the Playlists, and select from multiple available choices.
You can develop apps (smart contracts) in Python-like language, and use the PuyaPy compiler. You can also develop apps in a TypeScript like language, and use the TealScript compiler. There is a devepelopment framework called AlgoKit. It supports both PuyaPy and TealScript.
Algorand txn fee for a payment txn is 0.001 Algo, i.e. less then 0.0003 USD. And the cost to call an app (smart contract) depends from the number of inner transactions, so it is also low.
Although Algorand supports 10000 txn/sec, only a small fraction is used, typically less then 100 txn/sec , so the network is VERY lightly loaded, see e.g. Grafana
So there is virtually no congestion.
It you have an app (smart contract), you can use Tealer to check for the most common vulnerabilities.
I suggest to ask any questions on Algorand Discord
Here you can directly ask the devs. Also, there you can use kapa_ai, an intelligent bot.
Happy New Year!