I would like to fill a web form with values (the html code is the one below) but I don't know how to select an item in two fields that have values within a drop-down menu. The two fields that interest me are "Categories" and "Language". Can anyone suggest me how to do it? Thanks!
<form id='video_form' method='post' action='/admin/addvideo'
class='needs-validation' ><input id='save_request'
name='save_request' type='hidden' value='1'> <div
class='container'><div class='row
justify-content-start'><div class='col-12
text-center'><h2>Add New Video </h2></div></div><div
class='row justify-content-start'><div class='col-12
text-center'> </div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Title:</div><div class='col-9 text-left'><input
id='Title' name='Title' type='text' class='form-control
form-control-lg' placeholder='Title' value='' required >
<div class='invalid-tooltip'></div></div></div><div
class='row justify-content-start'><div class='col-12
text-center'> </div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Model:</div><div class='col-9 text-left'><input
id='Model' name='Model' type='text' class='form-control
form-control-lg' placeholder='Model' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Tags:</div><div class='col-9 text-left'><input
id='Tags' name='Tags' type='text' class='form-control
form-control-lg' placeholder='Tags' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Categories:</div><div class='col-9 text-left'>
<select class='form-control form-control-lg selectpicker'
multiple name='Categories[]' id='Categories'> <option
value='1896' >Anniversary & Celebrations</option>
<option value='1876' >Brand</option> <option value='1877'
>Clean Energy Leader</option> <option value='1893'
>Documentary</option> <option value='1882' >Events and
Shows</option> <option value='1879' >Historical</option>
<option value='1890' >Intro</option> <option value='1899'
>Performance test</option> <option value='1874'
>Plants</option> <option value='1880' >PLM</option>
<option value='1883' >Product Intro</option> <option
value='1881' >Product Launch</option> <option value='1898'
>Product overview</option> <option value='1884'
>Services</option> <option value='1894' >3D
Animation</option> <option value='1873' >Technical
Animation</option> <option value='1878'
>Testimonials</option> <option value='1895' >Training
Material</option> <option value='1892' >Walkaround with
voice over</option> <option value='1900' >Walk-In</option>
<option value='1897' >Web Series</option>
</select></div></div><div class='row
justify-content-start'><div class='col-12
text-center'> </div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Language:</div><div class='col-9 text-left'>
<select class='form-control' name='Language'
id='Language'> <option value='INT' >International (no
language)</option> <option value='INB' >English</option>
<option value='IOO' >Italian</option> <option value='DOO'
>German</option> <option value='FOO' >French</option>
<option value='BFO' >French for Belgium</option> <option
value='EOO' >Spanish</option> <option value='POO'
>Portuguese</option> <option value='NLO' >Dutch</option>
<option value='DKO' >Danish</option> <option value='SOO'
>Swedish</option> <option value='NOO' >Norwegian</option>
<option value='POL' >Polish</option> <option value='UKR'
>Ukrainian</option> <option value='HUN'
>Hungarian</option> <option value='CHZ' >Czech</option>
<option value='GRK' >Greek</option> <option value='ROM'
>Romanian</option> <option value='BRL' >Portuguese for
Brazil</option> <option value='LAT' >Spanish for
LATAM</option> <option value='MEX' >Spanish for
Mexico</option> <option value='CHI' >Chinese</option>
<option value='INC' >International Chinese</option>
<option value='JPN' >Japanese</option> <option value='KOR'
>Korean</option> <option value='CSI' >Russian</option>
<option value='HIN' >Hindi</option> <option value='MMR'
>Burmese</option> <option value='TUR' >Turkish</option>
</select></div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Publication Year:</div><div class='col-9
text-left'><input id='PublicationYear'
name='PublicationYear' type='text' class='form-control '
placeholder='Publication Year' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3 text-right'>Video
Length:</div><div class='col-9 text-left'><input
id='VideoLength' name='VideoLength' type='text'
class='form-control ' placeholder='Video Length' value='' >
<div class='invalid-tooltip'></div></div></div><div
class='row justify-content-start'><div class='col-3
text-right'>Music Details:</div><div class='col-9
text-left'><input id='MusicDetails' name='MusicDetails'
type='text' class='form-control ' placeholder='Music
Details' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-12
text-center'> </div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Location:</div><div class='col-9
text-left'><input id='Location' name='Location' type='text'
class='form-control ' placeholder='Location' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Director:</div><div class='col-9
text-left'><input id='Director' name='Director' type='text'
class='form-control ' placeholder='Director' value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3
text-right'>Production:</div><div class='col-9
text-left'><input id='Production' name='Production'
type='text' class='form-control ' placeholder='Production'
value='' > <div
class='invalid-tooltip'></div></div></div><div class='row
justify-content-start'><div class='col-3 text-right'>Web
format:</div><div class='col-9 text-left'> <select
class='form-control' name='WebFilename' id='WebFilename'>