These parts are not usually available for assembly by JLCPCB, so you need to order these from some where else and manually solder them to the modules
| Qty | Part | Footprint | LCSCStockCode | Part Number | Digikey | Mouser |
|---|---|---|---|---|---|---|
| 1 | ATtiny841-SSU | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | C219103 | ATtiny841-SSU | ATTINY841-SSU-ND | 556-ATTINY841-SSU |
| 4 | JST socket (Ext Temp) | Connector_JST:JST_PH_S2B-PH-K_1x02_P2.00mm_Horizontal | C265016 | S2B-PH-K(LF)(SN) | 455-1719-ND | PRT-09749 |
| 1 | AVR-ISP-6 | Pin_Headers:Pin_Header_Straight_2x03_Pitch2.54mm | C65114 | 1849-PR20203VBDN-ND | 649-1012938190601BLF |
You will also need some JST cables to connect the controller and modules together.
These have a FEMALE JST PH 2.0 2pin connector on them and are wired "straight through", that is, pin 1 goes to pin 1, 2 to 2.
You may be able to connect two of these cables together, take a look at Amazon
https://amzn.to/3dPgfxi (affiliate link)
Mouser seeedstudio part number for JST connector with pigtail 713-321050009