The closest open-source analog to TSMC 65nm is SkyWater 130nm. While it is older and larger, the design rules and tool flow (OpenLane, Magic VLSI) are identical to commercial flows.
Once approved, libraries are typically downloaded from a secure portal like (for EUROPRACTICE) or TSMC Online . TSMC - Europractice IC
The closest open-source analog to TSMC 65nm is SkyWater 130nm. While it is older and larger, the design rules and tool flow (OpenLane, Magic VLSI) are identical to commercial flows.
Once approved, libraries are typically downloaded from a secure portal like (for EUROPRACTICE) or TSMC Online . TSMC - Europractice IC tsmc 65nm standard cell library download