no acceleration car was sitting 6 months jumped to start enigine wont revonly goes about 20 mph,
A battery that has gone totally flat has severely less capacity, probably should be replaced.
Having said that. I suspect you have a CEL, you need to get the codes read and report those on this thread.
Most cars can survive sitting for 6 months, but Murphy’s Law still applies.
As a person that helps store a car for six months each year, I would first suspect that animals have made a nest inside your intake someplace. Could also be a many other things. Circle back and tell us after you or your mechanic find the cause(s).
How old is the gas in the tank? I have seen “fireproof” gasoline that is only 9 months old. Yours might be marginal.