Nǐ hǎo shìjiè (normally we don't greet like this, you can say here "da4 ji1a ha3o")

Wǒ xuéxí hànyǔ wǔ gè yuè le. Xiànza4i wǒ zhǐ xué pīnyīn, kěnéng yǐhòu wǒ ye3 kāishǐ xué hànzi.

Wǒ jīntiān zài zhèlǐ kāishi le xiě yīngyǔ le . Wǒ yīngyǔ bǐ wǒ hànyǔ hǎo hěn dūo, dànshi wǒ huì chángshì yòng hànyǔ xiě yíyàng de shi4qi3ngqi2ng. Ràng wǒmen lái kàn kàn.

Yīnwéi wǒde yīngyǔ bù jínbu3ji4nbu4(progress?). Wǒ dāyìng wǒ le wǒ zi4ji3 (myself) yì tiān zhìshǎo huì xiě yì ge jùzi. Wǒ bùshì duō huà de rén. Wǒ huì xiě shénme wǒ xiǎngdào nàgè shíhòu ji4u zhi1da4o le.

Wǒ xia3ng dui4 méi gè zhōngguǒ rén shūo duì bù qǐ  méi gè zhōngguǒ rén yīnwéi wǒ yòng nǐde yǔyànya2n (i don't understand why you were saying you feel sorry because you speak our language).
Suǒyǐ nǐ děi bàng wǒ jínbu3 ti2ga1o (improve) wǒde hànyǔ, nǐ za4i zhe4li ye3 kěyǐ kàn wo xiě de yīngyǔ, zhèyàng de huà ni3 kěnéng kàn de dǒng wǒ xiě de hànyǔ. Xiéxié Xie4Xie4

It's better to attach your English translation if necessary, and sometimes it's not easy to get your meaning, but in general it's fine. Hope you could learn to write Chinese characters soon.