tbh the 1st season is a game of trial and error. I would suggest picking some of the highest value players and also some high LA/PR players that already have decent est. value. Since young players improve fairly rapidly, high PR players that are okay at the beginning of the season may be top drawer by the end, so keep an eye on them. I would strongly suggest upgrading your scout so you can get scout reports with less energy...just one level drops the cost from 50 energy to 20. I can scout a few players for you each week and I think there are other managers who can as well...
For the first few weeks, try to pick as many players as possible. Make a spreadsheet to record skills and even calculate player abilities. From this pool of players select those that you think will be the best next season. Periodically re-select high LA players to monitor their progress. From all this form a core squad and tactical system you like. Finally, where possible, select high LA players on USA squads and give them some time on the pitch. As NT manager you have a unique power: by capping a player with the NT you ensure they will not be deleted from the game prior to their retirement. Every player that appears for his NT becomes a Free Player if his manager is banned or deleted.
A final word of advice: AVOID PLAYERS ON BOT TEAMS. If they avoid injury they will be 75% condition by mid-season. At the beginning of each season players are returned to 100% condition so don't be fooled. This is not as big of a problem as it was in the past but it is something to watch out for.