I am new here and I wanted to try this site.

You could say "I wanted", but it's better to keep everything in the present tense.

I wanted to improve my English and loste my fears abouto expressing myself in English.

"Express" can't be used alone in English. You need to express something.

I live in Germany in a small city aton the nNorth sSea.

The North Sea is a particular place, so its name needs to be capitalized.

I enjoy to watching the birds and insects in spring and summer.

With "enjoy", you need to use the gerund ("-ing"). By contrast, with "like", you can use either the gerund or the infinitive ("to watch").

Sometimes a cat from the neighbors is visting' place visits me and jumps on the bench.

"Sometimes" indicates a habitual occurrence, so you should use the simple present ("visits").

There is much work [to be done] in a garden.

However, I like also to sit there and read a book or drink a cup of tea and learnstudy English.

"Learn" means "acquire knowledge". "Study" means "put effort into trying to learn". In this case, "study" is better.

I wanted to improve my English and loste my fears to of expressing myself in English.

I don't think we ever use "express" intransitively, it needs an object. You could express your thoughts or express what you want to say, but the simplest thing is to just express yourself :)

I live in Germany in a small city atby the nNorth sSea.

Sometimes "on the North Sea".

I enjoy to watching the birds and insects in spring and summer.

I don't think there's a rule for this, unfortunately - you just have to remember that after some verbs you use the infinitive and after others you use the gerund. After "enjoy", you use the gerund.

Sometimes a cat from a neighbors i's vistingits me and jumps on the bench.

Simple present "visits" to express that this is something that happens habitually. You would use present progressive "is visiting" if you wanted to emphasise something that has a limited duration and is happening right now. Easier to make an example with "sitting": "I would get up, but my neighbour's cat is sitting on me."

Slightly more natural to say "Sometimes a neighbour's cat visits me".

There is much work's a lot of work to do in a garden.

I thought about this one for a long time! There isn't really an error, but it's not how I would naturally say it. I'd definitely change to "a lot", and adding "to do" makes it more clearly about how the work is required, that a garden is full of tasks that need *to be done*.

If I wanted to express this idea myself, I might be more likely to say "Gardens take a lot of work." Or maybe "A garden takes a lot of work." But I'm not sure.

However, I like alsoalso like to sit there and read a book or drink a cup of tea and learn English.

When it's an ordinary verb like "like", we very much prefer to have "also" in front of it rather than behind it.