Hi, could you please tell how to remove the bottom

if you mean the cover thats in behind the right road wheel then it is secured to the subframe with 1 torx screw and secured to the chassis at the top of the cover by 2 spider clips (circular metal clips) and it also clips to the bottom of the front bumper. unclip from the bumper, undo the screw and then pull the cover downwards to release the spider clips from the threaded studs. these can be real stubborn, but a good wrench downwards will release them.
which tensioner are you refering to - altanator drive or timing belt? it may be awkward to remove the timing cover bolt that is in behind the be alternator belt tensioner. if you want to remove it you will have to use a wrench to release the belt tension by swinging the tensionor pully away from the belt. there are two small holes that will line up when due swing it back suffeciently. this will allow you to insert a locking pin (or a drill bit) that will hold the tensioner back. only when this is done can the tensioner be removed. there are two types, the difference is in the bolt that holds it to the block. It will either be vissible from the front of the tensioner, the other type there is a 16 mm bolt that screws the other way and can be accessed from around the back of the tensioner, it is difficult to get on.

the one on the engine ?? two bolts either side ,cant remember but yes you may have to remove the fan belt tensioner thinking about it ,quick tip ?? to undo the bottom crank pulley bolt ,use a knuckle bar on socket and jam the knuckle bar into suspension then crank with starter motor ,undoes them everytime it does.Then before you slacken anything to do with the timing ,bring it around to TDC no 1 and paint all the pulleys to the block with white paint ,except the water pump and idlers .