Katakana is part of the Japanese writing system. Katakana is used mostly for foreign words and technical terms as opposed to Hiragana which is used mostly for native Japanese words. Katakana is derived from Kanji and usually are very angular with straight strokes.
“a” sound is like that in the word father.
“i” sound is like that found in feet.
“u” sound is like goo.
“e” sound is like in wet.
“o” sound is like that in slow.
If you can read then the rest should be pretty easy to pronounce. The vowel sounds are always the same they don’t make a million different sounds like in English. Although in some words the sound is made so quickly it is basically silent.
Well good luck to those wanting to learn, I hope this chart helps.