The latest average of polls has Labour in the lead:
Labour 25%
Conservative 23%
Brexit Party 21%
LDs 18%
Green 7%
(and, of course, parties such as the SNP, Plaid and the DUP, which are regional)
The percentages are so close that they're meaningless.. The FPTP system depends how concentrated in one area they are. There's always statistical error and people change their minds quite significantly if there's a new scandal!
Labour has a problem with Brexit. If it comes out as a Remain Party, it might pick up some votes/seats from the LDs, which might mean that the LDs lose out in LD/Con marginals. However, Labour would almost certainly also lose seats to the Brexit Party, especially in its northern heartlands. Meanwhile, the Brexit Party could very well lose votes back to the Conservatives, given the approach of the Johnson government. The vast majority of Labour voters are pro-Remain, but they're concentrated in areas such as London and Manchester, which are solidly Labour anyway.
Polls are a useless predictor of a GE result in the current climate.