Please find below the full walkthrough for the game N.E.R.D with each step with its own spoiler tag. If you need further assistance let me know in this thread!
N.E.R.D Walkthrough
Stage 1
1. ||Take out your phone.||
2. ||Check the calendar for the anniversary date.||
3. ||Turn on the flashlight.||
4. ||Enter the date into the padlock: 0108.||
5. ||Open the fridge and take all the items.||
6. ||Use the terrarium → feed the spider → take the tile.||
7. ||Use the desk → use the vase → take the paperclips.||
8. ||To find out the PC password, look through the SMS history with your brother on the smartphone. The password is NESBO.||
9. ||Change the date on the computer year by year, from 2012 to 2016, and look through the emails/files.||
10. ||Use the record player → pick Royal Blood → play “Careless.”||
11. ||Use the alarm clock → set it to 321.||
12. ||Find the favorite book in your brother's SMS history → use the bookcase → pick “Always in the Shadow” (“Zawsze w cieniu”).||
13. ||Use the alcohol bar → pick up the gas can → make a drink out of rum, water, ice, and lemon.||
14. ||Use the cabinet above the alcohol bar.||
15. ||Use the drawer under the TV.||
16. ||Correlate the bracelet coordinates with the list from time traveling on the PC → use the map → pick Ślęża.||
17. ||Use the cabinet above the bookcase.||
18. ||Use the desk → notebook → burn page D2.||
19. ||Use the radio → type in the favorite frequency (UKW 91.6).||
20. ||Use the box → type in OCATA.||
21. ||Use the desk → sharpen the pencil → use the sticky notes and scribble → call the number → check under the sofa.||
22. ||Use the painting with the TV → use the TV → press the button under 9 → press the colored buttons in the following order: green, red, blue, blue, yellow, red.||
23. ||Use the keyboard and play GAFC.||
24. ||Use the table → play Scrabble → place HAPPINESS on the board.||