Well, today hearToday, I listened to a podcast about the hobbies and want to share this, iwhat I learned. In thise podcast, they said that the hobbie is are activityies that we enjoy to practice andand to which we dedicated a lot of time in practicso we cand improve.

I don't think you need "well." It doesn't really add any meaning. The singular form of hobbies is hobby, but I want to say that I really do wish it was "hobbie" and then "hobbies" for plural. Many words that end in "y" have a plural where you drop the "y" and add "ies." For example, fly would be flies and fry would be fries. You can just stop at "enjoy", or you can say "enjoy doing." Since you are describing a hobby in the present tense (is an activity, enjoy), the other verbs should be in the present tense (dedicate instead of dedicated).

For example, my hobbiey is draw and painting over all scketch of modafashion illustration.

I wasn't quite sure what you were trying to say, so I took a wild guess that you meant fashion illustration.

Well, today hearToday I listened to a podcast about the hobbies and want to share this, in this podcast tabout it. They said that thea hobbiey is an activity that we enjoy to practiceing, and we dedicated a lot of time into practice and improve.

If you are talking about a movie, song, podcast, etc., then use the word "listen" instead of "hear." Before the word activity, you used "a" instead of "an." Basically, use "an" instead of "a" if the word after it starts with any vowel (letters a,e,i,o, and u)

For example, my hobbie iss are drawing and painting over all scketch of moda.

Use the word "hobbies" if you are talking about multiple activities and "hobby" if you are only talking about one activity. If you are talking about hobbies (multiple activities) then use the word "are" and if you're talking about a single activity, then use the word "is".