it's active in weekends

My level is high enough to join the 61-74 battlefields now but I still always get a message saying that not enough people joined.

go camp in 74

Thanks for all the advice.

If you want to farm battlefield points you might want to stop levelling once you get to level 74 or level 84 so that you can join the lower level battlefields because it's very difficult for new players to be competitive in the level 85 battlefields. You will need good armor and items that are properly carded and enhanced to stand a chance surviving.

Thanks. I'm glad it's just a matter of level.

Best is a matter of opinion. Easiest/fastest way is to buy with moolah (basically donations). Normal way is to go to battlefield. Your problem is you are low level. Battlefield is active for lvl 74ish bracket, level 75-84 and level 85. Rewards for winning there are several thousand points per run I believe, so you'll get quickly if you win. Just you need to level first. Quests in pvp maps... will take you half a year probably to get anything useful.