how do I adjust the linkage? on 1998 Chevrolet 1500 Pickup

Its becoming difficult to get into 1st &2nd & reverse on my 5-speed on the floor. When it engages, the truck goes like normal 233000 miles. I have been told to have the linkage adjusted. Or is it a bigger problem?

Possible clutch master/slave cylinder issue! Check fluid level, try pumping clutch pedal to see if it helps. Go into these gears ok with engine off?
1 more answer
not much adj poss bad shift cable or inside steering column is loose